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An electric motor operates at 20 r.p.s. What will be the approximate power delivered by the motor, if it supplies a torque of 75 N-m?
Three resistors are connected to form the sides of a triangle ABC, the resistance of the sides AB, BC and CA are 40 ohms, 60 ohms and 100 ohms respectively. The effective resistance between the points A and B in ohms will be
A piece of Aluminium and Germanium each are cooled from T1 k to T2 k. The resistance of
The ionisation potential of H-atom is 13.6V. When it is excited from ground state by monochromatic radiations of 970.6 Å, the number of emission lines will be (according to Bohr's theory)
The number of turs of primary and secondary coils of a transformer are 5 and 10 respectively and mutual inductance of the transformer is 25 H. Now, number of turns in primary and secondary are made 10 and 5 respectuvely. Mutual inductance of transformer will be
Threshold wavelength for photoelectric emission from a metal surface is 5200 Å. Photoelectrons will be emitted when this surface is illuminated with monochromatic radiation from
The capacitor of a parallel plate capacitor with no dielectric substance and a separation of 0.4 cm is 2 μF. The separation is reduced to half and it is filled with a substance of dielectric value 2.8. The new capacity of the capacitor is
We know that capacitance, c = Kε0A / d
Thus we get when K = 1 and d = 0.4 we get c = 2F
Thus let the value of c when K = 2.8 and d = 0.2 be z
Thus we get z/2 = (1 / 0.4) / (2.8 / 0.2)
Thus we get z = 2 x 5.6 F
= 11.2 F
Two concentric uniformly charged spheres of radius 5cm and 10cm are arranged as shown in the figure. Potential difference between the spheres is:
A block of mass 10 kg is placed on an inclined plane. When the angle of inclination is 30 o, the block just begins to side down the plane. The force of static friction is
Force of static friction f = μR
or f = mg sin θ, on point of sliding down of body.
∴ f = 10 x g x sin 30o
= 5(g) N = 5 kg wt.
The angular velocity of rotation of star at which the matter strat to escape from its equator will be
A perfect black body emits radiation at temperature 300 K. If it radiates 16 times this amount, then its temperature will be
One litre of Helium gas at a pressure 76 cm of Hg and temperture 27o is heated till its pressure and volume are doubled. The final temperature attained by the gas is
If current in a moving coil galvanometer is increased by 1%, then percentage increase in its deflection will be
A bar magnet is held perpendicular to a uniform magnetic field. If the couple acting on the magnet is to be halved by rotating it, then the angle by which it is to be rotated is
What should be the minimum average velocity of water in a small tube of radius 5 mm, so that the flow is just turbulent? (Given: Viscosity of water=0.01 poise and density of water = 1000 kg-m⁻3)
The neck and bottom of a bottle are 3 cm and 15 cm in radius respectively. If the cork is pressed with a force 12 N in the neck of the bottle, then force exerted on the bottom of the bottle is
Two similar wires under the same load yield elongations of 0.1 mm and 0.05 mm respectively. If the area of cross-section of the first wire is 4 mm2, then the area of cross-section of the second wire is
A stone is released from the top of a tower. If its velocity at half of the height is 10 m−s−1, then height of the tower is (Take g = 10 m−s−2)
For a particle in a uniformly accelerated circular motion
The resultant of two forces acting at an angle of 150o is 10 N and is perpendicular to one of the forces. The other force is
A body weighs 8 gm when placed in one pan and 18 gm when placed on the other pan of a false balance. If the beam is horizontal when both the pans are empty, the true weight of the body is
If the beam is horizontal, the apparent weight
The length of a telescope is 36 cm. The focal lengths of its lenses can be
A mass M is suspended from the spring of negligible mass. The spring is pulled a little and then released, so that the mass executes simple harmonic motion of time period T. If the mass is increased by m, the time period becomes 5T/3. The ratio m/M is
A body esecutes S.H.M. with amplitude A₀. At what displacement from the mean position, potential energy is one-fourth of its total energy?
A compound microscope has two lenses. The magnifying power of one is 5 and the combined magnifying power is 100. The magnifying power of the other lens is
A cylindrical solid of mass M has radius R and length L. Its moment of inertia about a generator is
Correct Answer : d
Explanation : Generator of axis of a cylinder is a line lying on its surface and parallel to axis of cylinder
By parallel axis theorem
I = (MR2 ) /2 + MR2
= 3/2MR2
Which of the following statements are correct when a gymnast sitting on a rotating stool with his arms outstretched, suddenly lowers his hands?
1. The angular velocity decreases.
2. The angular velocity increases.
3. The moment of inertia decreases.
4. The moment of inertia increases.
Select the answers using the codes given below.
Two identical particles move towards eachother with velocity 2ν and ν respectively. The velocity of centre of mass is
(1) The product of a volt and a coulomb is a joule.
(2) The product of a volt and an ampere is a joule/second
(3) The product of volt and watt is horse power.
(4) Watt-hour can be measured in terms of electron volt.
State if
Consider the following statements
Assertion (A) : In adiabatic compression, the internal energy and temperature of the system get decreased
Reason (R) : The adiabatic compression is a slow process
Of these statements
In a circuit, the resistance is 10.845Ω and current is 3.23 A. Its potential difference in four significant figures after rounding off, will be
If the ratio of intensities of two waves causing interference be 9:4, then the ratio of maximum and minimum intensities will be
If an open pipe of length l vibrates in fundamental mode, then pressure variation is maximum at
The potential energy of a weight less spring compressed by a distance a is propotional to
A ball moving with speed ν hits another identical ball at rest, The two balls stick together after collision. If specific heat of the material of the balls is S, the temperature rise resulting from the collision is
By conservation of momentum, final velocity=v/2
And by energy conservation,
Initial K.E=Final K.E+heat
A compound is soluble in conc. H₂SO₄, it does not decolourise bromine in carbon tetrachloride but is oxidised by chromic anhydride in aqueous sulphuric acid within two seconds, turning orange solution to blue, green and then opaque. The original compound is
Which of the following compounds does not react with NaHSO₃?
For 4f orbital n = 4, l = 4 – 1 = 3
Now, angular nodes = l = 3 and radial nodes = n – l – 1 = 0
Hence total nodes = 3
The uncertainty principle and the concept of wave nature of matter was proposed by........and........respectively
Molarity of liquid HCl with density equal to 1.17 g/cc is
Which of the following has the smallest number of molecules?
Which pair of species given below have identical bond order?
A and B are gaseous substances which react reversibly to give two gaseous substances C and D,accompanied by the liberation of heat.When the reaction reaches equilibrium,it is observed that Kp = Kc.The equilibrium cannot be disturbed by
Correct Answer : c
Explanation : A+B---> C+D
moles of reactant = 1+1 = 2
moles of product = 1+1 = 2
Suppose pressure is increased double, then volume will decrease to half
Let initial volume as V
final volume as V/2
k[initial] = [C][D]/[A][B]
= (nC/V*nD/V)/(nA/V*nB/V)
= (nCnD)/(nAnB)
k[final] = [C][D]/[A][B]
= (nc/(V/2)*nD/(V/2))/(nA/(V/2)*nB/(V*2))
= (ncnD)/(nAnB)
The rate of chemical reaction is doubled for every 10oC rise in temperature because of
Which of the following has the highest electronegativity?
Electronegativity of an element is the tendency of its atom to attract the shared pair of electrons towards itself in a covalent bond. The elements of highest electronegativity in the periodic table are:
F (4.0) > O (3.5) > Cl (3.0) = N (3.0) .
Standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are - 382.64 kJ mol-1 and - 145.6 JK-1 mol-1 respectively. The standard Gibbs energy change for the same reaction 298 K is
T = 298 K
ΔH = - 382.64 kJ mol-1
ΔS = - 145.6 JK-1 mol-1
= - 0.1456 kJ K-1 mol-1
ΔG = ΔH - TΔS
= -382.64 kJ mol-1 - (298 K) x (0.1456 k JK-1 mol-1)
= -382.64 kJ mol-1 + 43.3888 kJ mol-1
= -339.25 kJ mol-1 ≌ 339.3 kJrnol-1
Which of the following complexes will have four isomers?
(a) will have four different types of isomers
The lanthanide contraction is responsible for the fact that
When EoAg⁺/Ag = 0.80 V and EZn2⁺/Zn = - 0.76 V which of the following is correct ?
2-Methylbutane on reacting with bromine in the presence of sunlight gives mainly
Among the following compounds the one with the highest percentage of chlorine is
Oxalic acid reacts with concentrated H₂SO₄ to give a mixture of two gases. When this mixture is passed through caustic potash, one of the gases is absorbed. What is the product formed by the absorbed gas with caustic potash?
On heating mixture of NH4Cl and KNO2, N2 is obtained with potassium chloride and water.
NH4Cl+KNO2⟶N2+KCl+2H2O
Which one of the following properties is not correct for ozone?
BF₃ is used as a catalyst in several industrial processes due to its
The boron trihalides are covalent in nature and exist as monomeric molecules having planar triangular geometry. In these halides, boron assumes sp2 hybrid state and the three B−X bonds are formed by the axial overlap of sp2 hybrid orbital of boron and p-orbital of halogen as shown in Fig. Since there are only six electrons in the valence shell of a boron atom in boron trihalides, therefore, they have a great tendency to accept two more electrons in order to acquire stable octet.
Hence, boron trihalides act as Lewis acids. They rapidly combine with electron donors such as NH3, F−ion, amines, ether, sulphides or phosphorus.
Which of the following polymer is prepared from single monomer?
Which one of the following compounds liberates CO2 from aqueous NaHCO3
In Solvay process of manufacture of Na₂CO₃, the by products are
The molarity of a solution of Na₂CO₃ having 10.6 g/500 ml of solution is
In crystal structure of sodium chloride, the arrangement of Cl⁻ ion is
12 litre of hydrogen and 11.2 litre of chlorine are mixed and exploded. The composition in volume of the mixture will be
The area bounded by the parabola x = 4 - y2 and the y-axis in square units, is
In the expansion of (1+x+x2+x3)5 the sum of coefficients of even powers of x is :
The equation of the circle when touches x-axis at (3,0) and passing through (1,4) is
The solution of the equation y - x(dy/dx) = a[(y2)+(dy/dx)] is
The differential equation for the family of curves x2+ y2 - 2ay = 0, where a is an arbitrary constant is
The differential equation of family of curves y = a cos(x+b) is
In which interval function f(x)=2x3-15x2+36x+1 is decreasing
Sum of the given series
= (e2 - 1) - (e - 1) = e2 - e = e (e - 1)
The tangents to the hyperbola x2 - y2 = 3 are parallel to the st. line 2x + y + 8 = 0 at the following points
A flag staff 5m high is placed on a building 25m high. If flag and building both subtend equal angles on the observer at a height 30m, the distance between the observer and the top of the flag is
The area between (x2/a2) + (y2/b2) = 1 and the straight line (x/a) + (y/b) = 1 is
Solution of the equation (x + 2y3) (dy/dx) - y = 0 is (y > 0)
The sum of first 50 terms of the series cot⁻1 3 + cot⁻1 7 + cot⁻1 13 + cot⁻1 21 + ... is
The period of the function f(x) = sin(πx/2)+2 cos(πx/3)-tan(πx/4) is
If in a square matrix A=[aij], we find that
aij = aji ∀ i,j, then A is a
The point on the hyperbola (x2/24)-(y2/18)=1 which is nearest to the line 3x+2y+1=0 is
If angle between the lines 2x2+5xy+3y2+6x+7y+4=0 is tan⁻1m, the value of m is
The tangents at the points on the parabola y2 = 4 a x are at right angles if
The length of the normal chord to the parabola y2 = 4x which subtends a right angle at the vertex is
How many even numbers can be formed by using all the digits 2, 3, 4, 5, 6?
There are 16 points in a plane in which 6 are collinear. How many lines can be drawn by joining these points?
A box contains 10 good articles and 6 with defects. One item is drawn at random, what is the probability that it is either good or has a defect, is :
In eight throws of 1 die or 3 is considered a success. Then the standard deviation of the success is
In a triangle the line joining circum-centre and in-centre is parallel to BC, then cosB+cosC=
The sum of first n terms of the series (3/12) + (5/(12 + 22)) + (7/(12 + 22 + 32)) + ... is
Every term of a G.P. is positive and also every term is the sum of two preceding terms. Then the common ratio of the G.P. is
Let f (x) = (sin x)/(1 + √sinx). If D is the domain of f, then D contains
f(x)=x/(x-1)
f(x+1)=(x+1)/x (Put x = x+1)
Divide f(x) by f(x+1), we get => x^2 / (x^2 - 1)
Hence f(a)/f(a+1)= a^2 / (a^2 - 1) = f(a^2)
The equation of line passing through lines 5x-6y-1=0 and 3x+2y+5=0 and perpendicular to 3x-5y+11=0 is
The slope of the tangent of the locus y = cos-1 (cos x) at is
The direction cosines of a line equally inclined to the +ve directions of axes are
The centre of the sphere which passes through' four points (0,0,0),(0,2,0),(1,0,0) and (0,0,4) is
The general value of θ which satisfies the equations sinθ = -(1/2) and tanθ = (1/√3) is
If p=7i-2j+3k and q=3i+j+5k, then the modulus of p-2q is
Find the Antonym of the word occurring in the sentence in capital letter as per the context.
For the first time I saw him speaking RUDELY to her
'Rudely' means showing lack of respect.
So its antonym will be Politely
Fill in the blank with appropriate word.
It is difficult to believe what he tells us because his account of any event is always full of......of all sorts.
Fill in the blank with appropriate word.
Joseph introduced me .......... his mother as the best batsman.
Choose the one which can be substituted for the given words/sentences
A style full of words.
Choose the one which can be substituted for the given words/sentences
To take secretly in small quantities
So that he might top the list
Find the Synonym of the word occurring in the sentence in capital letter as per the context.
Very few people are IMPERVIOUS to criticism.
'Impervious' means inaccessible.
In the current context, the question word means 'not disturbed by'
Hence the correct answer options is Unaffected
Find the Synonym of the word occurring in the sentence in capital letter as per the context.
Her habits are INNOCUOUS.
'Innocuous' means not harmful or dangerous
Choose the pair in which the words are differently related .
Except Water : Tap
In all other pairs, second requires the first to function
Complete the analogous pair.
Gun : Bullet : : Chimney : ?
Group the following figures into three classes on the basis of identical properties.
1,3,6 contain one complete circle each.
2,5,7 contain a semi-circle each.
4,8,9 contain a triangle each.
In the first column, 17-11=25-19=6.
In the second column, 12-6=34-28=6.
Let the missing number in the third column be x.
Then, x-8=19-11=8 or x=16.
Find out the term in the number series which is wrong.
11, 2, 21, 3, 32, 4, 41, 5, 51, 6
The given sequence is a combination of two series :
I. 11, 21, 32, 41, 51
II. 2, 3, 4, 5, 6.
The pattern in I is + 10.
So, 32 is wrong and should be replaced by (21 + 10) i.e. 31
In this letter series, some of the letters are missing. Choose the correct letter given below -
b _ ac _ cc _ cb _ ab _ ac
Jogging, or running at an easy pace, is really popular now. It's fun, free and a quick way to get fit. It's very good for suppleness or upper body strength.
There's some risk of overuse injury to feet, knees, ankles and hips. But if you don't overdo it at first, and run on soft surface like grass when you can, you shouldn't have serious problems. If you have arthritis in your legs, hips or back or if you are overweight, try cycling or swimming instead.
The only expense is a good pair of running shoes. Avoid busy roads and jogging at night if possible. Wear light-coloured clothes so as not to feel uneasy and a cyclist's reflective chest band.
Q. Jogging is a popular exercise because it
Jogging, or running at an easy pace, is really popular now. It's fun, free and a quick way to get fit. It's very good for suppleness or upper body strength.
There's some risk of overuse injury to feet, knees, ankles and hips. But if you don't overdo it at first, and run on soft surface like grass when you can, you shouldn't have serious problems. If you have arthritis in your legs, hips or back or if you are overweight, try cycling or swimming instead.
The only expense is a good pair of running shoes. Avoid busy roads and jogging at night if possible. Wear light-coloured clothes so as not to feel uneasy and a cyclist's reflective chest band.
Q. Sometimes jogging can become risky when
Jogging, or running at an easy pace, is really popular now. It's fun, free and a quick way to get fit. It's very good for suppleness or upper body strength.
There's some risk of overuse injury to feet, knees, ankles and hips. But if you don't overdo it at first, and run on soft surface like grass when you can, you shouldn't have serious problems. If you have arthritis in your legs, hips or back or if you are overweight, try cycling or swimming instead.
The only expense is a good pair of running shoes. Avoid busy roads and jogging at night if possible. Wear light-coloured clothes so as not to feel uneasy and a cyclist's reflective chest band.
Q. Jogging is not advised for people who
Jogging, or running at an easy pace, is really popular now. It's fun, free and a quick way to get fit. It's very good for suppleness or upper body strength.
There's some risk of overuse injury to feet, knees, ankles and hips. But if you don't overdo it at first, and run on soft surface like grass when you can, you shouldn't have serious problems. If you have arthritis in your legs, hips or back or if you are overweight, try cycling or swimming instead.
The only expense is a good pair of running shoes. Avoid busy roads and jogging at night if possible. Wear light-coloured clothes so as not to feel uneasy and a cyclist's reflective chest band.
Q. Everybody can afford to jog as it
Select the correct mirror image of the figure (X) from amongst the given alternatives.
Each of the following questions consists of five Problem figures marked 1,2,3,4 and 5 followed by five Answer figures marked A,B,C,D and E . Select a figure from the Answer figures which will continue the same series as given in the Problem figures.
Each of the following questions consists of five Problem figures marked 1,2,3,4 and 5 followed by five Answer figures marked A,B,C,D and E . Select a figure from the Answer figures which will continue the same series as given in the Problem figures.
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