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All questions of IIT JAM Physics Mock Tests for Physics Exam
If the wave length of k∝ line silicon (z = 47) is 0.57 Å then the value of wavelength for uranium (z = 92) is
- a)2.28 Å
- b)1.28 Å
- c)2.53 Å
- d)0.146 Å
Correct answer is option 'D'. Can you explain this answer?
If the wave length of k∝ line silicon (z = 47) is 0.57 Å then the value of wavelength for uranium (z = 92) is
a)
2.28 Å
b)
1.28 Å
c)
2.53 Å
d)
0.146 Å
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Vedika Singh answered |
The wave length of k∝ line of an element is inversely proportional to its atomic number, or the number of protons in the element's nucleus. This means that as the atomic number of an element increases, the wave length of its k∝ line decreases. Therefore, to find the wave length of the k∝ line of an element with a given atomic number, you can use the following formula:
wave length = constant / atomic number
In this case, the wave length of the k∝ line of silicon (z = 47) is 0.57 Å, and the atomic number of uranium (z = 92) is greater than that of silicon. Using the formula above, we can calculate the wave length of the k∝ line of uranium as follows:
wave length = 0.57 Å / 92 wave length = 0.146 Å
Thus, the correct answer is 0.146 Å.
A collimated beam of light of diameter 2nm is propagating along the x - axis. The beam is to be expanded to a collimated beam of diameter 50nm using a combination of the convex lenses. A lens of focal length of 50 nm and another lens with focal length f are to be kept at a distance a between them. The value of F and d respectively are- a)450 nm and 105 nm
- b)400 nm and 500 nm
- c)550 nm and 600 nm
- d)1250 nm and 1300 nm
Correct answer is option 'D'. Can you explain this answer?
A collimated beam of light of diameter 2nm is propagating along the x - axis. The beam is to be expanded to a collimated beam of diameter 50nm using a combination of the convex lenses. A lens of focal length of 50 nm and another lens with focal length f are to be kept at a distance a between them. The value of F and d respectively are
a)
450 nm and 105 nm
b)
400 nm and 500 nm
c)
550 nm and 600 nm
d)
1250 nm and 1300 nm
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Vedika Singh answered |
F = 1250 nm
d = F + f = 1250 + 50 =1300nm
A metal sphere of radius ' a ' carries a charge Q as shown in figure. It is surrounded, out to radius b, by linear dielectric material of permittivity ' ∈ '. Choose the correct statements-- a)The potential at the centre relative to infinity is given by
- b)The electric field for a < r < b will be equal to the electric field for r > b.
- c)The surface charge density for dielectric at the outer surface will be
at the outer surface. - d)The volume charge density for dielectric is given by (ρ) = 0
Correct answer is option 'C,D'. Can you explain this answer?
A metal sphere of radius ' a ' carries a charge Q as shown in figure. It is surrounded, out to radius b, by linear dielectric material of permittivity ' ∈ '. Choose the correct statements-
a)
The potential at the centre relative to infinity is given by
b)
The electric field for a < r < b will be equal to the electric field for r > b.
c)
The surface charge density for dielectric at the outer surface will be at the outer surface.
at the outer surface.d)
The volume charge density for dielectric is given by (ρ) = 0
|
Pie Academy answered |
Inside the metal sphere of course E = P = D = 0
The potential at the centre is therefore:-
Now,
Thus
Option C,D is the only correct option,
When a fast moving neutron strikes a proton at rest. Which of the following are correct.- a)The collision between a neutron and a proton is perfectly elastic.
- b)The collision between a neutron and a proton is elastic.
- c)Neutron transfers almost whole of its K.E to proton.
- d)Neutrons will not transfer any energy to proton.
Correct answer is option 'A,C'. Can you explain this answer?
When a fast moving neutron strikes a proton at rest. Which of the following are correct.
a)
The collision between a neutron and a proton is perfectly elastic.
b)
The collision between a neutron and a proton is elastic.
c)
Neutron transfers almost whole of its K.E to proton.
d)
Neutrons will not transfer any energy to proton.
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Vedika Singh answered |
The collision between a neutron and a proton is perfectly elastic. In a perfectly elastic collision, the two colliding particles interchange their velocities, if their masses are equal.
Since proton and neutron have almost equal masses , they interchange their velocities. Thus practically neutron comes to rest and proton moves with the velocity of neutron. Hence neutron transfers almost whole of its K.E. to proton.
Since proton and neutron have almost equal masses , they interchange their velocities. Thus practically neutron comes to rest and proton moves with the velocity of neutron. Hence neutron transfers almost whole of its K.E. to proton.
The critical angle of light in a certain substance is 450. What is the polarizing angle?- a)540
- b)450
- c)600
- d)370
Correct answer is option 'A'. Can you explain this answer?
The critical angle of light in a certain substance is 450. What is the polarizing angle?
a)
540
b)
450
c)
600
d)
370
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|
Arghya answered |
The incident light is moving in the denser medium. If c be the critical angle, then we have 
where μ is the refractive index of the denser medium. Here c = 450.
If p be the polarising angle, then by Brewster's law, we have tan p = μ
where μ is the refractive index of the denser medium. Here c = 450.
If p be the polarising angle, then by Brewster's law, we have tan p = μ
In a double slit experiment two parallel slits are illuminated first by light of wacelength 400 nm and then by light of unknown wavelength. The fourth order dark fringe resuliting from the known wavelength of light falls in the same place on the screen as the second order bright fringe from the unknown wave length. The value of unknown wavelength of the light is - a)900 nm
- b)400 nm
- c)300 nm
- d)600 nm
Correct answer is option 'A'. Can you explain this answer?
In a double slit experiment two parallel slits are illuminated first by light of wacelength 400 nm and then by light of unknown wavelength. The fourth order dark fringe resuliting from the known wavelength of light falls in the same place on the screen as the second order bright fringe from the unknown wave length. The value of unknown wavelength of the light is
a)
900 nm
b)
400 nm
c)
300 nm
d)
600 nm
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Vedika Singh answered |
In a typical n-p-n transistor,the doping concentrations in emitter,base & collector regions are CE,CB & Cc respectively. These satisfy the relation:-- a)CE>Cc>CB
- b) CE> CB> CCC
- c)CC>CB>CE
- d)CE= CC> CB
Correct answer is option 'A'. Can you explain this answer?
In a typical n-p-n transistor,the doping concentrations in emitter,base & collector regions are CE,CB & Cc respectively. These satisfy the relation:-
a)
CE>Cc>CB
b)
CE> CB> CCC
c)
CC>CB>CE
d)
CE= CC> CB
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Vedika Singh answered |
In an n-p-n transistor emitter is heavily doped collector is moderately doped & base is very thin & least doped i.e.
CE>CC>CB
CE>CC>CB
If A body initially at rest ,is acted upon by an external force which is constant in magnitude.The gain in kinetic energy of the body at a given instant
- a)is directly proportional to the distance covered by it.
- b)is directly proportional to the time elapsed.
- c)is dependent on the time elapsed.
- d)is independent on the time elapsed.
Correct answer is option 'A,C'. Can you explain this answer?
If A body initially at rest ,is acted upon by an external force which is constant in magnitude.The gain in kinetic energy of the body at a given instant
a)
is directly proportional to the distance covered by it.
b)
is directly proportional to the time elapsed.
c)
is dependent on the time elapsed.
d)
is independent on the time elapsed.
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Vedika Singh answered |
Gain in kinetic energy by the particle is given by workdone by it from moving point x1, to x2.Thus , the gain in 
Now let force constant is k. Then kinetic energy
Thus K E α (x2-x1) in this relation it is clear that the K.E is directly proportional to the distance covered by it .
Now let force constant is k. Then kinetic energy
Thus K E α (x2-x1) in this relation it is clear that the K.E is directly proportional to the distance covered by it .
A cylinder of 1 kg mass and 0.02 m diameter left at the top of an inclined plane of height 1 m rolls down without slipping. Find the velocity (m/sec) of centre of mass of cylinder on reaching the bottom of inclined plane ___ .
Correct answer is '3.65'. Can you explain this answer?
A cylinder of 1 kg mass and 0.02 m diameter left at the top of an inclined plane of height 1 m rolls down without slipping. Find the velocity (m/sec) of centre of mass of cylinder on reaching the bottom of inclined plane ___ .
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Vedika Singh answered |
3.6 to 3.7
The kinetic energy of cylinder when it reaches the bottom = potential energy of the cylinder at the to p = mgh = 1 * 9.8 * 1 = 9.8 J
Kinetic energy KE = KE of translation + KE of rotation
Kinetic energy at bottom = 9.8 J
The kinetic energy of cylinder when it reaches the bottom = potential energy of the cylinder at the to p = mgh = 1 * 9.8 * 1 = 9.8 J
Kinetic energy KE = KE of translation + KE of rotation
Kinetic energy at bottom = 9.8 J
Two non-conducting solid sphere of radii R and 2R, having uniform volume charge densities P1 and P2 respectively, touch each other. The net electric field at a distance 2R from the centre of the smaller sphere, along the line joining the centre of the sphere, is zero. The ratio P1/P2 can be- a)-4
- b)-32/25
- c)32/25
- d)4
Correct answer is option 'B,C'. Can you explain this answer?
Two non-conducting solid sphere of radii R and 2R, having uniform volume charge densities P1 and P2 respectively, touch each other. The net electric field at a distance 2R from the centre of the smaller sphere, along the line joining the centre of the sphere, is zero. The ratio P1/P2 can be
a)
-4
b)
-32/25
c)
32/25
d)
4
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Vedika Singh answered |
If resultant electric field is zero, then
Two equally charged identical metal spheres A and B repel each other with a force 2 * 10-5 N. Another identical uncharged sphere C is touched to B and then placed at the mid point between A and B. The net electric force on C is ______ .- a)2 x 10-5N
- b)4 x 10-5N
- c)6 x 10-5N
- d)0
Correct answer is option 'A'. Can you explain this answer?
Two equally charged identical metal spheres A and B repel each other with a force 2 * 10-5 N. Another identical uncharged sphere C is touched to B and then placed at the mid point between A and B. The net electric force on C is ______ .
a)
2 x 10-5N
b)
4 x 10-5N
c)
6 x 10-5N
d)
0
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Vedika Singh answered |
As the sphere C is touched to sphere B ; the charge on B & C will be distributed equally.
A fast charged particle passes perpendicularly through a this glass sheet of refractive index 1.5. Inside the glass, the particle emits light. The minimum speed of the particle is- a)c/3
- b)2c/3
- c)4c/9
- d)c/9
Correct answer is option 'B'. Can you explain this answer?
A fast charged particle passes perpendicularly through a this glass sheet of refractive index 1.5. Inside the glass, the particle emits light. The minimum speed of the particle is
a)
c/3
b)
2c/3
c)
4c/9
d)
c/9
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Vedika Singh answered |
∴ regractive index n = c/v
An electromagnetic wave propagates through a non-magnetic medium which has two parameters. These are dielectric constant, ε and refractive index n. Which relations are incorrect?- a)ε2 = n
- b)√ε = n
- c)ε = Kn, where K is constant
- d)ε + n = 1
Correct answer is option 'A,C,D'. Can you explain this answer?
An electromagnetic wave propagates through a non-magnetic medium which has two parameters. These are dielectric constant, ε and refractive index n. Which relations are incorrect?
a)
ε2 = n
b)
√ε = n
c)
ε = Kn, where K is constant
d)
ε + n = 1
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Vedika Singh answered |
In an Electromagnetic wave is propagated through a non - conducting magnetic medium of dielectric constant ε & of refracting index n then they are related as refractive index (n): -
then incorrect options are
then incorrect options are
A neutron of mass mn = 10-27 kg is moving inside a nucleus. Assume the nucleus to be a cubical box of size 10-14 m with impenetrable walls. Take 
Js and 1 MeV ≈ 10-13 J . An estimate of the energy in Mev of the neutron is- a)80 MeV
- b)1/8 MeV
- c)8 MeV
- d)1/80 MeV
Correct answer is option 'B'. Can you explain this answer?
A neutron of mass mn = 10-27 kg is moving inside a nucleus. Assume the nucleus to be a cubical box of size 10-14 m with impenetrable walls. Take Js and 1 MeV ≈ 10-13 J . An estimate of the energy in Mev of the neutron is
Js and 1 MeV ≈ 10-13 J . An estimate of the energy in Mev of the neutron isa)
80 MeV
b)
1/8 MeV
c)
8 MeV
d)
1/80 MeV
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Pie Academy answered |
Plance polarized light passes through a quartz plate its optic axis parallel to the faces. Then calculate the least thickness of the plate for which emergent beam will be plane polarized and circularly polarized
- a)
- b)
- c)
- d)
Correct answer is option 'A,C'. Can you explain this answer?
Plance polarized light passes through a quartz plate its optic axis parallel to the faces. Then calculate the least thickness of the plate for which emergent beam will be plane polarized and circularly polarized
a)
b)
c)
d)
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Pie Academy answered |
A train is moving at 30m/s in still air. The frequency of the locomotive whistle is 500Hz & The speed of the sound is 345m/s. Then which of the following statement is correct: -- a)The apparent wavelengths of sound in front of locomotive are ”0.60 m".
- b)The apparent wavelength behind the locomotive is respectively 0.75m.
- c)If a wind of speed 10m/s is blowing in the same direction as that in which the locomotive is travelling the apparent wavelength in front of the locomotive will be 0.65m.
- d)In the case of wind flowing the apparent wavelength behind the locomotive is 0.63m.
Correct answer is option 'B,C'. Can you explain this answer?
A train is moving at 30m/s in still air. The frequency of the locomotive whistle is 500Hz & The speed of the sound is 345m/s. Then which of the following statement is correct: -
a)
The apparent wavelengths of sound in front of locomotive are ”0.60 m".
b)
The apparent wavelength behind the locomotive is respectively 0.75m.
c)
If a wind of speed 10m/s is blowing in the same direction as that in which the locomotive is travelling the apparent wavelength in front of the locomotive will be 0.65m.
d)
In the case of wind flowing the apparent wavelength behind the locomotive is 0.63m.
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Vedika Singh answered |
are only correct option.
In still air :- (1) front of locomotive:-
= λ' = 0.75m
In case of wind :- (1) front of locomotive:-
(ii) behind the locomotive:- c' = c-vwind = 355m
In still air :- (1) front of locomotive:-
= λ' = 0.75m
In case of wind :- (1) front of locomotive:-
(ii) behind the locomotive:- c' = c-vwind = 355m
A chain is used to lower a block of mass m through a distance h at a constant acceleration of g/5. What is the work done by the chain on the block?- a)-mgh/5
- b)-4mgh/5
- c)mgh/5
- d)4mgh/5
Correct answer is option 'B'. Can you explain this answer?
A chain is used to lower a block of mass m through a distance h at a constant acceleration of g/5. What is the work done by the chain on the block?
a)
-mgh/5
b)
-4mgh/5
c)
mgh/5
d)
4mgh/5
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Vedika Singh answered |
Work done by the chain = mgh/5
Real work done by the chain = mgh
work done by the chain on the block is
Real work done by the chain = mgh
work done by the chain on the block is
An n-type silicon rod of length 0.7 cm has a cross sectional area of 0.1cm2. A DC bias voltage of 35v across on the rod results in a 5.6 ampere DC current. Under this DC bias, an electric pulse applied at one end takes 10μ sec to traverse the length of silicon rod, then the mobility of the charge carrier is ____.
Correct answer is '0.14'. Can you explain this answer?
An n-type silicon rod of length 0.7 cm has a cross sectional area of 0.1cm2. A DC bias voltage of 35v across on the rod results in a 5.6 ampere DC current. Under this DC bias, an electric pulse applied at one end takes 10μ sec to traverse the length of silicon rod, then the mobility of the charge carrier is ____.
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Arghya answered |
are two quantum mechanical operators. If 
stands for the commutator of 
then 
is equal to ________ .
Consider the following statements associated with the basic properties of conductors & choose the correct statements:-- a)The net charge density in the interior is zero.
- b)While considering the field boundary conditions, the tangential component of electric field is continuous across the boundary between two dielectrics.
- c)The dielectric material is in a state of compression.
- d)The discontinuity in the normal component of the flux density at a dielectric - conductor boundary is equal to the surface charge density on the conductor.
Correct answer is option 'A,B,C,D'. Can you explain this answer?
Consider the following statements associated with the basic properties of conductors & choose the correct statements:-
a)
The net charge density in the interior is zero.
b)
While considering the field boundary conditions, the tangential component of electric field is continuous across the boundary between two dielectrics.
c)
The dielectric material is in a state of compression.
d)
The discontinuity in the normal component of the flux density at a dielectric - conductor boundary is equal to the surface charge density on the conductor.
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Vedika Singh answered |
(i) The resultant field inside the ideal conductor is zero.
(ii) The tangential component of E.F at the boundary are discontinuous by the surface current density, the surface current flow only in high conductivity media ; therefore (ii) is correct.
(iii) Because of Electrostriction effect the dielectric material be a state of compression.
(iv) The displacement flux densities normal component at the boundary are discontinuous by surface charge density.
(ii) The tangential component of E.F at the boundary are discontinuous by the surface current density, the surface current flow only in high conductivity media ; therefore (ii) is correct.
(iii) Because of Electrostriction effect the dielectric material be a state of compression.
(iv) The displacement flux densities normal component at the boundary are discontinuous by surface charge density.
A rocket of total initial mass mo is expelling exhaust gas at a steady speed 2.88 m /sec with respect to itself, when its mass is reduced to 1/2 m0, the velocity attained by the rocket will be ______ (in m/sec).
Correct answer is '2'. Can you explain this answer?
A rocket of total initial mass mo is expelling exhaust gas at a steady speed 2.88 m /sec with respect to itself, when its mass is reduced to 1/2 m0, the velocity attained by the rocket will be ______ (in m/sec).
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Vedika Singh answered |
Formula for rocket is given as
putting in eq.(1) we get
putting in eq.(1) we get
A source of sound frequency 256 Hz is moving rapidly towards a wall with a velocity of 5 m/sec. If velocity of sound is 330 m/sec. The number of beats per second heard by an observer behind the source is ____ Hz.
Correct answer is '7.7'. Can you explain this answer?
A source of sound frequency 256 Hz is moving rapidly towards a wall with a velocity of 5 m/sec. If velocity of sound is 330 m/sec. The number of beats per second heard by an observer behind the source is ____ Hz.
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Vedika Singh answered |
An observer behind the source will hear two seconds one of the frequency
and the other of frequency
and the other of frequency
A particle moves along the curve X = 2t2. y = t2 - 4t, z = 3t - 5 where t is time. Find the velocity and acceleration at t = 1 in the direction of 
- a)
- b)
- c)
- d)
Correct answer is option 'B,C'. Can you explain this answer?
A particle moves along the curve X = 2t2. y = t2 - 4t, z = 3t - 5 where t is time. Find the velocity and acceleration at t = 1 in the direction of
a)
b)
c)
d)
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Vedika Singh answered |
The velocity component are given by
at t = 1
Now the component of velocity in the direction of
and the component of acceleration in the direction of
at t = 1
Now the component of velocity in the direction of
and the component of acceleration in the direction of
The black body spectrum of an object P is radiant intensity at maximum wavelength of 100 nm. Another object Q has the maximum radiant intensity at 400 nm. What will be the ratio of power emitted per unit area by P to that of Q?- a)16 : 1
- b)256 : 1
- c)25 : 1
- d)64 : 1
Correct answer is option 'B'. Can you explain this answer?
The black body spectrum of an object P is radiant intensity at maximum wavelength of 100 nm. Another object Q has the maximum radiant intensity at 400 nm. What will be the ratio of power emitted per unit area by P to that of Q?
a)
16 : 1
b)
256 : 1
c)
25 : 1
d)
64 : 1
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Mister Genius answered |
From wein’s displacement law
A young's double slit apparatus has a slit separation of 0.4 mm and a screen placed at a distance of 200 cm from the slits. When illuminated by a 632 nm Helium Neon laser, the position of the first intensity minimum with respect to the central maximum will be- a)632 μm
- b)1580 μm
- c)918 μm
- d)740 μm
Correct answer is option 'B'. Can you explain this answer?
A young's double slit apparatus has a slit separation of 0.4 mm and a screen placed at a distance of 200 cm from the slits. When illuminated by a 632 nm Helium Neon laser, the position of the first intensity minimum with respect to the central maximum will be
a)
632 μm
b)
1580 μm
c)
918 μm
d)
740 μm
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Vedika Singh answered |
A proton and an α-particle. accelerated through the same potential difference, enter a region of uniform magnetic field normally. If the radius of the proton orbit is 10 cm that of the α-orbit , then radius of proton orbit is- a)10 cm
- b)10√2 cm
- c)20 cm
- d)5√2 cm
Correct answer is option 'B'. Can you explain this answer?
A proton and an α-particle. accelerated through the same potential difference, enter a region of uniform magnetic field normally. If the radius of the proton orbit is 10 cm that of the α-orbit , then radius of proton orbit is
a)
10 cm
b)
10√2 cm
c)
20 cm
d)
5√2 cm
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Vedika Singh answered |
Which of the following statement(s)related toBrownian motion is/are incorrect?- a)It is result of combined effect of chemical electrical and gravitational forces.
- b)Brownian speed increases if the vessels containing gas is shaken violently.
- c)Brownian motion is faster if the viscosity is low.
- d)Brownian speed increases if the pressure difference between particles and points of a container is increased
Correct answer is option 'A,B,C'. Can you explain this answer?
Which of the following statement(s)related toBrownian motion is/are incorrect?
a)
It is result of combined effect of chemical electrical and gravitational forces.
b)
Brownian speed increases if the vessels containing gas is shaken violently.
c)
Brownian motion is faster if the viscosity is low.
d)
Brownian speed increases if the pressure difference between particles and points of a container is increased
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Vedika Singh answered |
To and fro motion of colloidal particles in the solution is called Brownian motion.The size of the particles in colloidal solution is of the order of 104 em.This is a chemical and gravitational phenomenon not electrical phenomenon.Brownian motion is independent of the motion of vessel containing gas Displacement is Brownian motion is given by
Where η is viscosity.Thus .Brownian motion is inversely proportional to η hence Brownian motion increase on decreasing viscosity.
Where η is viscosity.Thus .Brownian motion is inversely proportional to η hence Brownian motion increase on decreasing viscosity.
Which of the following statements is/are correct:-- a)Mass and energy of a moving object are dependent entities.
- b)Massless particle can exists only if they move with the speed of light.
- c)The relative velocity of two photons approaching each other is equal to the velocity of light.
- d)Mass and energy of a moving object are independent entities.
Correct answer is option 'A,B,C'. Can you explain this answer?
Which of the following statements is/are correct:-
a)
Mass and energy of a moving object are dependent entities.
b)
Massless particle can exists only if they move with the speed of light.
c)
The relative velocity of two photons approaching each other is equal to the velocity of light.
d)
Mass and energy of a moving object are independent entities.
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Vedika Singh answered |
(A) If the object is moving its total energy is E = mc2 = 
So, mass and energy of an moving object are dependant entities. When mass is being created or destroyed an equivalent amount of energy Simultaneously vanished or created and vice versa.
(B) We know that
That means the speed of a massless particle is always equals to the speed of light. Massless particle can exists only if they move with the speed of light. (C) we know that inverse lorentz transformation are
So, the relative velocity of two photons approaching each other is equal to the velocity of light.
So, mass and energy of an moving object are dependant entities. When mass is being created or destroyed an equivalent amount of energy Simultaneously vanished or created and vice versa.
(B) We know that
That means the speed of a massless particle is always equals to the speed of light. Massless particle can exists only if they move with the speed of light. (C) we know that inverse lorentz transformation are
So, the relative velocity of two photons approaching each other is equal to the velocity of light.
Consider the following statement for a particle moving in an elliptic orbit under the influence of a central force. Which of the following statement(s) is/are correct?- a)The radius vector covers equal area in equal time
- b)The motion takes place in a plane
- c)The angular momentum is a constant of motion
- d)The path of a particle under the influence of a central force must lie in a plane.
Correct answer is option 'A,B,C'. Can you explain this answer?
Consider the following statement for a particle moving in an elliptic orbit under the influence of a central force. Which of the following statement(s) is/are correct?
a)
The radius vector covers equal area in equal time
b)
The motion takes place in a plane
c)
The angular momentum is a constant of motion
d)
The path of a particle under the influence of a central force must lie in a plane.
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Vedika Singh answered |
We have angular momentum,
Two condensers of capacitances 2μF and 3μF are charged to potentials 100 V and 200 V respectively. They are then joined in parallel in such a way that plates which have positive charges are connected together. The energy dissipated into heat in the process is_____. write in milli Joule.
Correct answer is '6'. Can you explain this answer?
Two condensers of capacitances 2μF and 3μF are charged to potentials 100 V and 200 V respectively. They are then joined in parallel in such a way that plates which have positive charges are connected together. The energy dissipated into heat in the process is_____. write in milli Joule.
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Pie Academy answered |
Then energy dissipation is given as
Consider the following in respect of compton scattering and zeeman effect, which of the following statement(s) is/are incorrect?- a)Compton scattering formula holds less and less rigorously as we go towards longer wavelengths.
- b)collision between a photon and an electron is inelastic
- c)Each energy level in the atom is split into just three level which are equally spaced
- d)The spacing between split levels is directly proportional to the applied magnetic field.
Correct answer is option 'A,B,C'. Can you explain this answer?
Consider the following in respect of compton scattering and zeeman effect, which of the following statement(s) is/are incorrect?
a)
Compton scattering formula holds less and less rigorously as we go towards longer wavelengths.
b)
collision between a photon and an electron is inelastic
c)
Each energy level in the atom is split into just three level which are equally spaced
d)
The spacing between split levels is directly proportional to the applied magnetic field.
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Vedika Singh answered |
Compton scattering formula holds less and less rigorous to go towards longer wavelength but it has shorter wavelength.collision between photons is inelastic but it is elastic in nature . when an atom is placed in external magnetic field the spectral lines it emits are split into several polarized components.This effect of magnetic field on the atomic spectral lines is called zeeman effect.
A singlet spectral line viewed normal to the field is split into three plane- polarised components, a central unshift line with the electric vector vibrating parallel to the field and two other lines equally displaced one on either side with electric vector perpendicular to the field.
A singlet spectral line viewed normal to the field is split into three plane- polarised components, a central unshift line with the electric vector vibrating parallel to the field and two other lines equally displaced one on either side with electric vector perpendicular to the field.
How many lines per centimetre are there in a plane transmission granting which gives 1st order of light of wavelength 6000 
at angle of diffraction 300?- a)8000 lines/cm
- b)8333 lines/cm
- c)8200 lines/cm
- d)8433 lines/cm
Correct answer is option 'B'. Can you explain this answer?
How many lines per centimetre are there in a plane transmission granting which gives 1st order of light of wavelength 6000 at angle of diffraction 300?
at angle of diffraction 300?a)
8000 lines/cm
b)
8333 lines/cm
c)
8200 lines/cm
d)
8433 lines/cm
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Vedika Singh answered |
The plane grating equation is,
∴ Grating element,
Since the getting element is equal to the reciprocal of the number of lines per cm. Therefore, number of lines per cm
Hence, the maximum number of orders visible in the spectrum are 19.
∴ Grating element,
Since the getting element is equal to the reciprocal of the number of lines per cm. Therefore, number of lines per cm
Hence, the maximum number of orders visible in the spectrum are 19.
Consider a one - dimensional harmonic oscillator of angular frequency ω. If 5 identical electrons occupy the energy levels of this oscillator at zero temperature,
Then the ground state energy E0 = ______
Correct answer is '13'. Can you explain this answer?
Consider a one - dimensional harmonic oscillator of angular frequency ω. If 5 identical electrons occupy the energy levels of this oscillator at zero temperature,
Then the ground state energy E0 = ______
Then the ground state energy E0 = ______
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Pie Academy answered |
For one-dimensional harmonic oscillator 
A stone of mass 5 kg is placed at a distance 5m from the axis of rotaion on the rotating table ( angular velocity w with respect to earth) What would be the angular velocity w so that the stone starts slipping? {The frictional coefficient between stone and table is 1.5 }- a)1.7 rad/sec
- b)1.5 rad/sec
- c)1.2 rad/sec
- d)None
Correct answer is option 'A'. Can you explain this answer?
A stone of mass 5 kg is placed at a distance 5m from the axis of rotaion on the rotating table ( angular velocity w with respect to earth) What would be the angular velocity w so that the stone starts slipping? {The frictional coefficient between stone and table is 1.5 }
a)
1.7 rad/sec
b)
1.5 rad/sec
c)
1.2 rad/sec
d)
None
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Vedika Singh answered |
If the stone starts slipping, then the centripetl force will be equal to the frictional force.
For the given op-amp circuit (we have given value as 
A01 = 200000), choose the correct statement:-
- a)The input impedance is 17.4GΩ.
- b)The output impedance is 8.6Ω.
- c)The closed loop voltage gain is 23.0 (approx).
- d)Input impendance decreases while the output impedance increases.
Correct answer is option 'A,C'. Can you explain this answer?
For the given op-amp circuit (we have given value as A01 = 200000), choose the correct statement:-
A01 = 200000), choose the correct statement:-a)
The input impedance is 17.4GΩ.
b)
The output impedance is 8.6Ω.
c)
The closed loop voltage gain is 23.0 (approx).
d)
Input impendance decreases while the output impedance increases.
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Pie Academy answered |
are only correct.
The attenuation B, of the feed back circuit
The attenuation B, of the feed back circuit
The eiqen values and eigen vectors of the matrix 
are- a)6,1 and
- b)2 ,5 and
- c)6,1 and
- d)2,5 and
Correct answer is option 'A'. Can you explain this answer?
The eiqen values and eigen vectors of the matrix are
area)
6,1 and
b)
2 ,5 and
c)
6,1 and
d)
2,5 and
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Vedika Singh answered |
The characteristic equation is 
λ = 1,6
Eigen vector corresponding to the eigen value λ = 1 by putting λ = 1 ,the matrix becomes
⇒ X = K, V= -K
Eigen vector x1 is
Now again Eigen vector corresponding to the eigenvalue λ = 6, By putting λ = 6
λ = 1,6
Eigen vector corresponding to the eigen value λ = 1 by putting λ = 1 ,the matrix becomes
⇒ X = K, V= -K
Eigen vector x1 is
Now again Eigen vector corresponding to the eigenvalue λ = 6, By putting λ = 6
Which of the following statement (s) is / are correct?- a)If the electric field due to a point charge varies as r-5/2 instead of. then the Gauss’s law will shall be valid
- b)The Gauss’s law can be used to calculate the field distribution around an electric dipole.
- c)If the electric field between two point charges is zero somewhere, then the sign of two charges is the same.
- d)The work done by the external force in moving a unit positive charge from point A at potential VA to point B at potential VB is (VB - VA) .
Correct answer is option 'C,D'. Can you explain this answer?
Which of the following statement (s) is / are correct?
a)
If the electric field due to a point charge varies as r-5/2 instead of. then the Gauss’s law will shall be valid
b)
The Gauss’s law can be used to calculate the field distribution around an electric dipole.
c)
If the electric field between two point charges is zero somewhere, then the sign of two charges is the same.
d)
The work done by the external force in moving a unit positive charge from point A at potential VA to point B at potential VB is (VB - VA) .
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Vedika Singh answered |
If q1 and q2 are like charges then electric field between two point changes is zero somewhere. The workdone is moving a unit positive charge unaccelerated i.e. it remains in the state of quasistatic equilibrium which happens if force applied by external agency
The velocity of extraordinary ray in calcite crystal in a plane perpenducular to the optic axis. Given 
- a)2.02 x 1010 cm/s
- b)2.38 x 1010 cm/s
- c)3.02 x 1010
- d)3.38 x 1010 cm/s
Correct answer is option 'A'. Can you explain this answer?
The velocity of extraordinary ray in calcite crystal in a plane perpenducular to the optic axis. Given
a)
2.02 x 1010 cm/s
b)
2.38 x 1010 cm/s
c)
3.02 x 1010
d)
3.38 x 1010 cm/s
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Mister Genius answered |
The velocity of the O-wave in the crystal is
The velocity of the E-wave in the crystal normal to be optic axis is
The velocity of the E-wave in the crystal normal to be optic axis is
Two glass bulbs of equal volumes are connected by a narrow tube and are filled with a gas at o0C and a pressure of 76cm of Hg. One of the bulbs is then placed in water both maintained at 620C, what is the new value of pressure inside the bulbs (in cm of Hg)? (The volume of connecting tube is negligible.)
Correct answer is '83.75'. Can you explain this answer?
Two glass bulbs of equal volumes are connected by a narrow tube and are filled with a gas at o0C and a pressure of 76cm of Hg. One of the bulbs is then placed in water both maintained at 620C, what is the new value of pressure inside the bulbs (in cm of Hg)? (The volume of connecting tube is negligible.)
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Vedika Singh answered |
PV = nRT
As total number of air molecules in the bulbs would remain constant, we have
As temperature of second bulb is uncharged, we have
As total number of air molecules in the bulbs would remain constant, we have
As temperature of second bulb is uncharged, we have
If the ice on the polar caps of the earth melts then which of the following statement is/are correct:-- a)The moment of inertia of the earth about its own axis, increases
- b)Angular momentum is conserved
- c)The angular velocity of earth about its own axis decreases
- d)Duration of the day will increase.
Correct answer is option 'A,B,C,D'. Can you explain this answer?
If the ice on the polar caps of the earth melts then which of the following statement is/are correct:-
a)
The moment of inertia of the earth about its own axis, increases
b)
Angular momentum is conserved
c)
The angular velocity of earth about its own axis decreases
d)
Duration of the day will increase.
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Vedika Singh answered |
If the ice on the polar caps of the earth melts, the water so formed will spread on the surface of earth . This increases the moment of inertia of the earth about its own axis due to change in the distribution of mass of the particles of water going away from the axis of rotation. To conseive angular momentum angular velocity of earth about its own axis will decrease. As 
Hence due to decrease in the value of ω, the duration of the day will increase.
Hence due to decrease in the value of ω, the duration of the day will increase.
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IIT JAM Physics Mock Test Series 2026
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