NEET Exam > NEET Notes > Additional Study Material for NEET > CBSE Physics Past year paper - 2015, Class 12
CBSE Physics Past year paper - 2015, Class 12 | Additional Study Material for NEET PDF Download
| Download, print and study this document offline |
Please wait while the PDF view is loading
Page 1
CBSE XII | PHYSICS
Board Paper – 2015
CBSE
Class XII Physics
Board Paper – 2015
Time: 3 hours Maximum Marks: 70
General Instructions:
(i) All questions are compulsory. There are 26 questions in all.
(ii) This question paper has five sections: Section A, Section B, Section, Section D and
Section E.
(iii) Section A contains five questions of one mark each, section B contains five questions
of two marks each, section C contains twelve questions of three marks each, section
D contains one value based question of four marks and section E contains three
questions of five marks each.
(iv) There is no overall choice. However, an internal choice has been provided in one
question of two marks, one question of three marks and all the three questions of five
marks weightage. You have to attempt only one of the choices in such questions.
(v) You may use the following values of physical constants wherever necessary:
c = 3 ? 10
8
m/s
h = 6.63 ? 10
-34
Js
e = 1.6 ? 10
-19
C
µ 0 = 4 p ? 10
-7
T mA
-l
? 0 = 8.854 ? 10
-12
C
2
N
-1
m
-2
0
1
4 ??
= 9 ? 10
9
N m
2
C
-2
m e = 9.1 ? 10
-31
kg
Mass of neutron = 1.675 ? 10
-27
kg
Mass of proton = 1.673 ? 10
-27
kg
Avogadro’s number = 6.023 ? 10
23
per gram mole
Boltzmann constant = 1.38 ? 10
-23
J K
-1
SECTION – A
Q. 1 Define the term ‘mobility’ of charge carriers. Write its S.I. unit [1]
Q. 2 In a series LCR circuit, V L = V C ? V R. What is the value of power factor? [1]
Q. 3 The focal length of an equiconvex lens is equal to the radius of curvature of either face.
What is the refractive index of the material of the lens? [1]
Q. 4 Write a relation for polarisation P of a dielectric material in the presence of an
external electric field E . [1]
Page 2
CBSE XII | PHYSICS
Board Paper – 2015
CBSE
Class XII Physics
Board Paper – 2015
Time: 3 hours Maximum Marks: 70
General Instructions:
(i) All questions are compulsory. There are 26 questions in all.
(ii) This question paper has five sections: Section A, Section B, Section, Section D and
Section E.
(iii) Section A contains five questions of one mark each, section B contains five questions
of two marks each, section C contains twelve questions of three marks each, section
D contains one value based question of four marks and section E contains three
questions of five marks each.
(iv) There is no overall choice. However, an internal choice has been provided in one
question of two marks, one question of three marks and all the three questions of five
marks weightage. You have to attempt only one of the choices in such questions.
(v) You may use the following values of physical constants wherever necessary:
c = 3 ? 10
8
m/s
h = 6.63 ? 10
-34
Js
e = 1.6 ? 10
-19
C
µ 0 = 4 p ? 10
-7
T mA
-l
? 0 = 8.854 ? 10
-12
C
2
N
-1
m
-2
0
1
4 ??
= 9 ? 10
9
N m
2
C
-2
m e = 9.1 ? 10
-31
kg
Mass of neutron = 1.675 ? 10
-27
kg
Mass of proton = 1.673 ? 10
-27
kg
Avogadro’s number = 6.023 ? 10
23
per gram mole
Boltzmann constant = 1.38 ? 10
-23
J K
-1
SECTION – A
Q. 1 Define the term ‘mobility’ of charge carriers. Write its S.I. unit [1]
Q. 2 In a series LCR circuit, V L = V C ? V R. What is the value of power factor? [1]
Q. 3 The focal length of an equiconvex lens is equal to the radius of curvature of either face.
What is the refractive index of the material of the lens? [1]
Q. 4 Write a relation for polarisation P of a dielectric material in the presence of an
external electric field E . [1]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 5 What happens when a forward bias is applied to a p-n junction? [1]
SECTION – B
Q. 6 [2]
(a) Distinguish between ‘Analog’ and ‘Digital’ forms of communication.
(b) Explain briefly two commonly used applications of the ‘Internet’.
Q. 7 Given the ground state energy E 0 = - 13.6 eV and Bohr radius a 0 = 0.53
o
A . Find out how
the de Broglie wavelength associated with the electron orbiting in the ground state
would change when it jumps into the first excited state. [2]
Q. 8 State Bohr’s postulate of hydrogen atom which successfully explains the emission lines
in the spectrum of hydrogen atom.
Use Rydberg formula to determine the wavelength of H
? line.
[Given: Rydberg constant R = 1.03 × 10
7
m
-1
] [2]
Q. 9 State the two Kirchhoff’s rules used in electric networks. How are there rules justified?
[2]
Q. 10 Write the important characteristic features by which the interference can be
distinguished from the observed diffraction pattern. [2]
OR
Explain the basic differences between the construction and working of a telescope
and a microscope. [2]
SECTION – C
Q. 11 Light of intensity ‘I’ and frequency ‘ ?’ is incident on a photosensitive surface and
causes photoelectric emission. What will be the effect on anode current when (i) the
intensity of light is gradually increased, (ii) the frequency of incident radiation is
increased, and (iii) the anode potential is increased? In each case, all other factors
remain the same.
Explain, giving justification in each case. [3]
Q. 12 When is a transistor said to be in active state? Draw a circuit diagram of a p-n-p
transistor and explain how it works as a transistor amplifier. Write clearly, why in
the case of a transistor (i) the base is thin and lightly doped and (ii) the emitter is
heavily doped. [3]
Page 3
CBSE XII | PHYSICS
Board Paper – 2015
CBSE
Class XII Physics
Board Paper – 2015
Time: 3 hours Maximum Marks: 70
General Instructions:
(i) All questions are compulsory. There are 26 questions in all.
(ii) This question paper has five sections: Section A, Section B, Section, Section D and
Section E.
(iii) Section A contains five questions of one mark each, section B contains five questions
of two marks each, section C contains twelve questions of three marks each, section
D contains one value based question of four marks and section E contains three
questions of five marks each.
(iv) There is no overall choice. However, an internal choice has been provided in one
question of two marks, one question of three marks and all the three questions of five
marks weightage. You have to attempt only one of the choices in such questions.
(v) You may use the following values of physical constants wherever necessary:
c = 3 ? 10
8
m/s
h = 6.63 ? 10
-34
Js
e = 1.6 ? 10
-19
C
µ 0 = 4 p ? 10
-7
T mA
-l
? 0 = 8.854 ? 10
-12
C
2
N
-1
m
-2
0
1
4 ??
= 9 ? 10
9
N m
2
C
-2
m e = 9.1 ? 10
-31
kg
Mass of neutron = 1.675 ? 10
-27
kg
Mass of proton = 1.673 ? 10
-27
kg
Avogadro’s number = 6.023 ? 10
23
per gram mole
Boltzmann constant = 1.38 ? 10
-23
J K
-1
SECTION – A
Q. 1 Define the term ‘mobility’ of charge carriers. Write its S.I. unit [1]
Q. 2 In a series LCR circuit, V L = V C ? V R. What is the value of power factor? [1]
Q. 3 The focal length of an equiconvex lens is equal to the radius of curvature of either face.
What is the refractive index of the material of the lens? [1]
Q. 4 Write a relation for polarisation P of a dielectric material in the presence of an
external electric field E . [1]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 5 What happens when a forward bias is applied to a p-n junction? [1]
SECTION – B
Q. 6 [2]
(a) Distinguish between ‘Analog’ and ‘Digital’ forms of communication.
(b) Explain briefly two commonly used applications of the ‘Internet’.
Q. 7 Given the ground state energy E 0 = - 13.6 eV and Bohr radius a 0 = 0.53
o
A . Find out how
the de Broglie wavelength associated with the electron orbiting in the ground state
would change when it jumps into the first excited state. [2]
Q. 8 State Bohr’s postulate of hydrogen atom which successfully explains the emission lines
in the spectrum of hydrogen atom.
Use Rydberg formula to determine the wavelength of H
? line.
[Given: Rydberg constant R = 1.03 × 10
7
m
-1
] [2]
Q. 9 State the two Kirchhoff’s rules used in electric networks. How are there rules justified?
[2]
Q. 10 Write the important characteristic features by which the interference can be
distinguished from the observed diffraction pattern. [2]
OR
Explain the basic differences between the construction and working of a telescope
and a microscope. [2]
SECTION – C
Q. 11 Light of intensity ‘I’ and frequency ‘ ?’ is incident on a photosensitive surface and
causes photoelectric emission. What will be the effect on anode current when (i) the
intensity of light is gradually increased, (ii) the frequency of incident radiation is
increased, and (iii) the anode potential is increased? In each case, all other factors
remain the same.
Explain, giving justification in each case. [3]
Q. 12 When is a transistor said to be in active state? Draw a circuit diagram of a p-n-p
transistor and explain how it works as a transistor amplifier. Write clearly, why in
the case of a transistor (i) the base is thin and lightly doped and (ii) the emitter is
heavily doped. [3]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 13
(a) State three important factors showing the need for translating a low frequency
signal into a high frequency wave before transmission.
(b) Draw a sketch of a sinusoidal carrier wave along with a modulating signal and show
how these are superimposed to obtain the resultant amplitude modulated wave. [3]
Q. 14 You are given three circuit elements X, Y and Z. When the element X is connected
across an a.c. source of a given voltage, the current and the voltage are in the same
phase. When the element Y is connected in series with X across the source, voltage is
ahead of the current in phase by /4 ? . But the current is ahead of the voltage in
phase by /4 ? when Z is connected in series with X across the source. Identify the
circuit elements X, Y and Z.
When all the three elements are connected in series across the same source,
determine the impedance of the circuit.
Draw a plot of the current versus the frequency of applied source and mention the
significance of this plot. [3]
Q. 15 plot a graph showing the variation of current density (j) versus the electric field (E)
for two conductors of different materials. What information from this plot regarding
the properties of the conducting material, can be obtained which can be used to
select suitable materials for use in making (i) standard resistance and (ii)
connecting wires in electric circuits?
Electron drift speed is estimated to be of the order of mm s
-1
. Yet large current of
the order of few amperes can be set up in the wire. Explain briefly. [3]
Q. 16 State Biot – Savart law. Deduce the expression for the magnetic field at a point on the
axis of a current carrying circular loop of radius ‘R’ distant ‘x’ from the centre. Hence,
write the magnetic field at the centre of a loop. [3]
Q. 17 What dose a polaroid consist of? Show, using a simple polaroid, that light waves are
transverse in nature. Intensity of light coming out of a polaroid does not change
irrespective of the orientation of the pass axis of the polaroid. Explain why. [3]
Q. 18 How is a Zener diode fabricated? What causes the setting up of high electric field
even for small reverse bias voltage across the diode?
Describe, with the help of a circuit diagram, the working of Zener diode as a voltage
regulator. [3]
OR
(a) Explain with the help of a diagram, how depletion region and potential barrier
are formed in a junction diode.
(b) If a small voltage is applied to a p-n junction diode, how will the barrier potential
be affected when it is (i) forward biased, and (ii) reveres biased? [3]
Page 4
CBSE XII | PHYSICS
Board Paper – 2015
CBSE
Class XII Physics
Board Paper – 2015
Time: 3 hours Maximum Marks: 70
General Instructions:
(i) All questions are compulsory. There are 26 questions in all.
(ii) This question paper has five sections: Section A, Section B, Section, Section D and
Section E.
(iii) Section A contains five questions of one mark each, section B contains five questions
of two marks each, section C contains twelve questions of three marks each, section
D contains one value based question of four marks and section E contains three
questions of five marks each.
(iv) There is no overall choice. However, an internal choice has been provided in one
question of two marks, one question of three marks and all the three questions of five
marks weightage. You have to attempt only one of the choices in such questions.
(v) You may use the following values of physical constants wherever necessary:
c = 3 ? 10
8
m/s
h = 6.63 ? 10
-34
Js
e = 1.6 ? 10
-19
C
µ 0 = 4 p ? 10
-7
T mA
-l
? 0 = 8.854 ? 10
-12
C
2
N
-1
m
-2
0
1
4 ??
= 9 ? 10
9
N m
2
C
-2
m e = 9.1 ? 10
-31
kg
Mass of neutron = 1.675 ? 10
-27
kg
Mass of proton = 1.673 ? 10
-27
kg
Avogadro’s number = 6.023 ? 10
23
per gram mole
Boltzmann constant = 1.38 ? 10
-23
J K
-1
SECTION – A
Q. 1 Define the term ‘mobility’ of charge carriers. Write its S.I. unit [1]
Q. 2 In a series LCR circuit, V L = V C ? V R. What is the value of power factor? [1]
Q. 3 The focal length of an equiconvex lens is equal to the radius of curvature of either face.
What is the refractive index of the material of the lens? [1]
Q. 4 Write a relation for polarisation P of a dielectric material in the presence of an
external electric field E . [1]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 5 What happens when a forward bias is applied to a p-n junction? [1]
SECTION – B
Q. 6 [2]
(a) Distinguish between ‘Analog’ and ‘Digital’ forms of communication.
(b) Explain briefly two commonly used applications of the ‘Internet’.
Q. 7 Given the ground state energy E 0 = - 13.6 eV and Bohr radius a 0 = 0.53
o
A . Find out how
the de Broglie wavelength associated with the electron orbiting in the ground state
would change when it jumps into the first excited state. [2]
Q. 8 State Bohr’s postulate of hydrogen atom which successfully explains the emission lines
in the spectrum of hydrogen atom.
Use Rydberg formula to determine the wavelength of H
? line.
[Given: Rydberg constant R = 1.03 × 10
7
m
-1
] [2]
Q. 9 State the two Kirchhoff’s rules used in electric networks. How are there rules justified?
[2]
Q. 10 Write the important characteristic features by which the interference can be
distinguished from the observed diffraction pattern. [2]
OR
Explain the basic differences between the construction and working of a telescope
and a microscope. [2]
SECTION – C
Q. 11 Light of intensity ‘I’ and frequency ‘ ?’ is incident on a photosensitive surface and
causes photoelectric emission. What will be the effect on anode current when (i) the
intensity of light is gradually increased, (ii) the frequency of incident radiation is
increased, and (iii) the anode potential is increased? In each case, all other factors
remain the same.
Explain, giving justification in each case. [3]
Q. 12 When is a transistor said to be in active state? Draw a circuit diagram of a p-n-p
transistor and explain how it works as a transistor amplifier. Write clearly, why in
the case of a transistor (i) the base is thin and lightly doped and (ii) the emitter is
heavily doped. [3]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 13
(a) State three important factors showing the need for translating a low frequency
signal into a high frequency wave before transmission.
(b) Draw a sketch of a sinusoidal carrier wave along with a modulating signal and show
how these are superimposed to obtain the resultant amplitude modulated wave. [3]
Q. 14 You are given three circuit elements X, Y and Z. When the element X is connected
across an a.c. source of a given voltage, the current and the voltage are in the same
phase. When the element Y is connected in series with X across the source, voltage is
ahead of the current in phase by /4 ? . But the current is ahead of the voltage in
phase by /4 ? when Z is connected in series with X across the source. Identify the
circuit elements X, Y and Z.
When all the three elements are connected in series across the same source,
determine the impedance of the circuit.
Draw a plot of the current versus the frequency of applied source and mention the
significance of this plot. [3]
Q. 15 plot a graph showing the variation of current density (j) versus the electric field (E)
for two conductors of different materials. What information from this plot regarding
the properties of the conducting material, can be obtained which can be used to
select suitable materials for use in making (i) standard resistance and (ii)
connecting wires in electric circuits?
Electron drift speed is estimated to be of the order of mm s
-1
. Yet large current of
the order of few amperes can be set up in the wire. Explain briefly. [3]
Q. 16 State Biot – Savart law. Deduce the expression for the magnetic field at a point on the
axis of a current carrying circular loop of radius ‘R’ distant ‘x’ from the centre. Hence,
write the magnetic field at the centre of a loop. [3]
Q. 17 What dose a polaroid consist of? Show, using a simple polaroid, that light waves are
transverse in nature. Intensity of light coming out of a polaroid does not change
irrespective of the orientation of the pass axis of the polaroid. Explain why. [3]
Q. 18 How is a Zener diode fabricated? What causes the setting up of high electric field
even for small reverse bias voltage across the diode?
Describe, with the help of a circuit diagram, the working of Zener diode as a voltage
regulator. [3]
OR
(a) Explain with the help of a diagram, how depletion region and potential barrier
are formed in a junction diode.
(b) If a small voltage is applied to a p-n junction diode, how will the barrier potential
be affected when it is (i) forward biased, and (ii) reveres biased? [3]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 19 Arrange the following electromagnetic wave in the order of their increasing
wavelength:
(a) ?- rays
(b) Microwaves
(c) X-rays
(d) Radio waves
How are infra-red waves produced? What role dose infra-red radiation play in (i)
maintain the Earth’s warmth and (ii) physical therapy? [3]
Q. 20 Explain briefly the process of charging a parallel plate capacitor when it is connected
across a d.c. battery.
A capacitor of capacitance ‘C’ is charged to ‘V’ volts by a battery. After some time the
battery is disconnected and the distance between the plates is doubled. Now a slab of
dielectric constant, 1 < k < 2, is introduced to fill the space between the plates. How
will the following be affected?
(a) The electric field between the plates of the capacitor
(b) The energy stored in the capacitor
Justify your answer by writing the necessary expressions. [3]
Q. 21 Write symbolically the nuclear ß
+
decay process of
11
6
C . Is the decayed product X an
isotope or isobar of (
11
6
C )? Given the mass values m (
11
6
C ) = 11.011434 u and
m (X) = 11.009305 u. Estimate the Q-value in this process. [3]
Q. 22 An object is placed 15 cm in front of a convex lens of focal length 10 cm. Find the
nature and position of the image formed. Where should a concave mirror of radius
of curvature 20 cm be placed so that the final image is formed at the position of the
object itself? [3]
SECTION – D
Q. 23 Ajit had a high tension tower erected on his farm land. He kept complaining to the
authorities to remove it as it was occupying a large portion of his land. His uncle,
who was a teacher, explained to him the need for erecting these towers for efficient
transmission of power. As Ajit realised its significance, he stopped complaining.
Answer the following questions: [4]
(a) Why is it necessary to transport power at high voltage?
(b) A low power factor implies large power loss. Explain.
(c) Write two values each displayed by Ajit and his uncle.
Page 5
CBSE XII | PHYSICS
Board Paper – 2015
CBSE
Class XII Physics
Board Paper – 2015
Time: 3 hours Maximum Marks: 70
General Instructions:
(i) All questions are compulsory. There are 26 questions in all.
(ii) This question paper has five sections: Section A, Section B, Section, Section D and
Section E.
(iii) Section A contains five questions of one mark each, section B contains five questions
of two marks each, section C contains twelve questions of three marks each, section
D contains one value based question of four marks and section E contains three
questions of five marks each.
(iv) There is no overall choice. However, an internal choice has been provided in one
question of two marks, one question of three marks and all the three questions of five
marks weightage. You have to attempt only one of the choices in such questions.
(v) You may use the following values of physical constants wherever necessary:
c = 3 ? 10
8
m/s
h = 6.63 ? 10
-34
Js
e = 1.6 ? 10
-19
C
µ 0 = 4 p ? 10
-7
T mA
-l
? 0 = 8.854 ? 10
-12
C
2
N
-1
m
-2
0
1
4 ??
= 9 ? 10
9
N m
2
C
-2
m e = 9.1 ? 10
-31
kg
Mass of neutron = 1.675 ? 10
-27
kg
Mass of proton = 1.673 ? 10
-27
kg
Avogadro’s number = 6.023 ? 10
23
per gram mole
Boltzmann constant = 1.38 ? 10
-23
J K
-1
SECTION – A
Q. 1 Define the term ‘mobility’ of charge carriers. Write its S.I. unit [1]
Q. 2 In a series LCR circuit, V L = V C ? V R. What is the value of power factor? [1]
Q. 3 The focal length of an equiconvex lens is equal to the radius of curvature of either face.
What is the refractive index of the material of the lens? [1]
Q. 4 Write a relation for polarisation P of a dielectric material in the presence of an
external electric field E . [1]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 5 What happens when a forward bias is applied to a p-n junction? [1]
SECTION – B
Q. 6 [2]
(a) Distinguish between ‘Analog’ and ‘Digital’ forms of communication.
(b) Explain briefly two commonly used applications of the ‘Internet’.
Q. 7 Given the ground state energy E 0 = - 13.6 eV and Bohr radius a 0 = 0.53
o
A . Find out how
the de Broglie wavelength associated with the electron orbiting in the ground state
would change when it jumps into the first excited state. [2]
Q. 8 State Bohr’s postulate of hydrogen atom which successfully explains the emission lines
in the spectrum of hydrogen atom.
Use Rydberg formula to determine the wavelength of H
? line.
[Given: Rydberg constant R = 1.03 × 10
7
m
-1
] [2]
Q. 9 State the two Kirchhoff’s rules used in electric networks. How are there rules justified?
[2]
Q. 10 Write the important characteristic features by which the interference can be
distinguished from the observed diffraction pattern. [2]
OR
Explain the basic differences between the construction and working of a telescope
and a microscope. [2]
SECTION – C
Q. 11 Light of intensity ‘I’ and frequency ‘ ?’ is incident on a photosensitive surface and
causes photoelectric emission. What will be the effect on anode current when (i) the
intensity of light is gradually increased, (ii) the frequency of incident radiation is
increased, and (iii) the anode potential is increased? In each case, all other factors
remain the same.
Explain, giving justification in each case. [3]
Q. 12 When is a transistor said to be in active state? Draw a circuit diagram of a p-n-p
transistor and explain how it works as a transistor amplifier. Write clearly, why in
the case of a transistor (i) the base is thin and lightly doped and (ii) the emitter is
heavily doped. [3]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 13
(a) State three important factors showing the need for translating a low frequency
signal into a high frequency wave before transmission.
(b) Draw a sketch of a sinusoidal carrier wave along with a modulating signal and show
how these are superimposed to obtain the resultant amplitude modulated wave. [3]
Q. 14 You are given three circuit elements X, Y and Z. When the element X is connected
across an a.c. source of a given voltage, the current and the voltage are in the same
phase. When the element Y is connected in series with X across the source, voltage is
ahead of the current in phase by /4 ? . But the current is ahead of the voltage in
phase by /4 ? when Z is connected in series with X across the source. Identify the
circuit elements X, Y and Z.
When all the three elements are connected in series across the same source,
determine the impedance of the circuit.
Draw a plot of the current versus the frequency of applied source and mention the
significance of this plot. [3]
Q. 15 plot a graph showing the variation of current density (j) versus the electric field (E)
for two conductors of different materials. What information from this plot regarding
the properties of the conducting material, can be obtained which can be used to
select suitable materials for use in making (i) standard resistance and (ii)
connecting wires in electric circuits?
Electron drift speed is estimated to be of the order of mm s
-1
. Yet large current of
the order of few amperes can be set up in the wire. Explain briefly. [3]
Q. 16 State Biot – Savart law. Deduce the expression for the magnetic field at a point on the
axis of a current carrying circular loop of radius ‘R’ distant ‘x’ from the centre. Hence,
write the magnetic field at the centre of a loop. [3]
Q. 17 What dose a polaroid consist of? Show, using a simple polaroid, that light waves are
transverse in nature. Intensity of light coming out of a polaroid does not change
irrespective of the orientation of the pass axis of the polaroid. Explain why. [3]
Q. 18 How is a Zener diode fabricated? What causes the setting up of high electric field
even for small reverse bias voltage across the diode?
Describe, with the help of a circuit diagram, the working of Zener diode as a voltage
regulator. [3]
OR
(a) Explain with the help of a diagram, how depletion region and potential barrier
are formed in a junction diode.
(b) If a small voltage is applied to a p-n junction diode, how will the barrier potential
be affected when it is (i) forward biased, and (ii) reveres biased? [3]
CBSE XII | PHYSICS
Board Paper – 2015
Q. 19 Arrange the following electromagnetic wave in the order of their increasing
wavelength:
(a) ?- rays
(b) Microwaves
(c) X-rays
(d) Radio waves
How are infra-red waves produced? What role dose infra-red radiation play in (i)
maintain the Earth’s warmth and (ii) physical therapy? [3]
Q. 20 Explain briefly the process of charging a parallel plate capacitor when it is connected
across a d.c. battery.
A capacitor of capacitance ‘C’ is charged to ‘V’ volts by a battery. After some time the
battery is disconnected and the distance between the plates is doubled. Now a slab of
dielectric constant, 1 < k < 2, is introduced to fill the space between the plates. How
will the following be affected?
(a) The electric field between the plates of the capacitor
(b) The energy stored in the capacitor
Justify your answer by writing the necessary expressions. [3]
Q. 21 Write symbolically the nuclear ß
+
decay process of
11
6
C . Is the decayed product X an
isotope or isobar of (
11
6
C )? Given the mass values m (
11
6
C ) = 11.011434 u and
m (X) = 11.009305 u. Estimate the Q-value in this process. [3]
Q. 22 An object is placed 15 cm in front of a convex lens of focal length 10 cm. Find the
nature and position of the image formed. Where should a concave mirror of radius
of curvature 20 cm be placed so that the final image is formed at the position of the
object itself? [3]
SECTION – D
Q. 23 Ajit had a high tension tower erected on his farm land. He kept complaining to the
authorities to remove it as it was occupying a large portion of his land. His uncle,
who was a teacher, explained to him the need for erecting these towers for efficient
transmission of power. As Ajit realised its significance, he stopped complaining.
Answer the following questions: [4]
(a) Why is it necessary to transport power at high voltage?
(b) A low power factor implies large power loss. Explain.
(c) Write two values each displayed by Ajit and his uncle.
CBSE XII | PHYSICS
Board Paper – 2015
SECTION – E
Q. 24
(a) Deduce the expression for the potential energy of a system of two charges q 1 and q 2
located
1
r and
2
r , respectively, in an external electric field.
(b) Three point charges, + Q + 2Q and – 3Q are placed at the vertices of an equilateral
triangle ABC of side l. If these charges are displaced to the mid-point A 1, B 1 and C 1,
respectively, find the amount of the work done in shifting the charges to the new
locations.
OR
Define electric flux. Write its S.I unit.
State and explain Gauss’s law. Find out the outward flux to a point charge +q placed at
the centre of a cube of side ‘a’. Why is it found to be independent of the size and shape
of the surface enclosing it? Explain. [5]
Q. 25
(a) Define self-inductance of a coil. Obtain an expression for the energy stored in a
solenoid of self-inductance ‘L’ when the current though it grows from zero to ‘I’.
(b) A square loop MNOP of side 20 cm is placed horizontally in a uniform magnetic field
acting vertically downwards as shown in the figure. The loop is pulled with a
constant velocity of 20 cm s
-1
till it goes out of the field.
Read More
|
26 videos|287 docs|64 tests
|
FAQs on CBSE Physics Past year paper - 2015, Class 12 - Additional Study Material for NEET
| 1. What are the important topics to study in CBSE Physics Class 12 exam? |  |
Ans. Some important topics to study for the CBSE Physics Class 12 exam include electric charges and fields, electromagnetic induction, optics, dual nature of matter and radiation, atoms and nuclei, and electronic devices.
| 2. How can I prepare effectively for the CBSE Physics Class 12 exam? | |
Ans. To prepare effectively for the CBSE Physics Class 12 exam, it is important to have a clear understanding of the concepts. Start by thoroughly studying the NCERT textbooks and make notes of important points. Practice solving previous year question papers and sample papers to get familiar with the exam pattern and improve time management skills. Additionally, revise regularly and solve numerical problems to strengthen your problem-solving abilities.
| 3. What are some important tips for scoring well in the CBSE Physics Class 12 exam? | |
Ans. Some important tips for scoring well in the CBSE Physics Class 12 exam are:
- Understand the concepts thoroughly and focus on the important topics.
- Practice solving numerical problems to enhance your problem-solving skills.
- Solve previous year question papers to get acquainted with the exam pattern and identify the important topics.
- Make concise notes while studying and revise them regularly.
- Manage your time effectively during the exam and allocate enough time for each section.
- Use diagrams and labeled illustrations wherever necessary to enhance your answers.
| 4. Are there any recommended reference books for CBSE Physics Class 12 exam preparation? | |
Ans. While the NCERT textbooks are sufficient for CBSE Physics Class 12 exam preparation, some students might find it helpful to refer to additional reference books for a deeper understanding of certain topics. Some popular reference books for CBSE Physics Class 12 exam include "Concepts of Physics" by H.C. Verma, "Fundamentals of Physics" by Halliday, Resnick, and Walker, and "Physics for Class XII" by P. L. Sahu.
| 5. How can I improve my problem-solving skills in CBSE Physics Class 12 exam? | |
Ans. To improve your problem-solving skills in the CBSE Physics Class 12 exam, it is important to practice solving a variety of numerical problems. Start by understanding the concepts and principles behind each topic and then attempt different types of numerical problems related to those topics. Analyze the steps required to solve each problem and practice using the appropriate formulas and equations. Additionally, solve previous year question papers and sample papers to get familiar with the types of problems frequently asked in the exam.
About this Document
|
4.91/5 Rating |
|
Nov 21, 2024 Last updated |
Document Description: CBSE Physics Past year paper - 2015, Class 12 for NEET 2024 is part of Additional Study Material for NEET preparation.
The notes and questions for CBSE Physics Past year paper - 2015, Class 12 have been prepared according to the NEET exam syllabus. Information about CBSE Physics Past year paper - 2015, Class 12 covers topics
like and CBSE Physics Past year paper - 2015, Class 12 Example, for NEET 2024 Exam. Find important definitions, questions, notes, meanings, examples, exercises and tests below for CBSE Physics Past year paper - 2015, Class 12.
Introduction of CBSE Physics Past year paper - 2015, Class 12 in English is available as part of our Additional Study Material for NEET
for NEET & CBSE Physics Past year paper - 2015, Class 12 in Hindi for Additional Study Material for NEET course.
Download more important topics related with notes, lectures and mock test series for NEET
Exam by signing up for free. NEET: CBSE Physics Past year paper - 2015, Class 12 | Additional Study Material for NEET
Description
Full syllabus notes, lecture & questions for CBSE Physics Past year paper - 2015, Class 12 | Additional Study Material for NEET - NEET | Plus excerises question with solution to help you revise complete syllabus for Additional Study Material for NEET | Best notes, free PDF download
Information about CBSE Physics Past year paper - 2015, Class 12
In this doc you can find the meaning of CBSE Physics Past year paper - 2015, Class 12 defined & explained in the simplest way possible. Besides explaining types of
CBSE Physics Past year paper - 2015, Class 12 theory, EduRev gives you an ample number of questions to practice CBSE Physics Past year paper - 2015, Class 12 tests, examples and also practice NEET
tests
|
Explore Courses for NEET exam
|
|
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
Related Searches
video lectures
,Previous Year Questions with Solutions
,shortcuts and tricks
,Exam
,Summary
,Class 12 | Additional Study Material for NEET
,CBSE Physics Past year paper - 2015
,Class 12 | Additional Study Material for NEET
,mock tests for examination
,practice quizzes
,Free
,Viva Questions
,ppt
,Class 12 | Additional Study Material for NEET
,Important questions
,MCQs
,Objective type Questions
,CBSE Physics Past year paper - 2015
,CBSE Physics Past year paper - 2015
,Sample Paper
,Extra Questions
,study material
,past year papers
,Semester Notes
;
Additional Information about CBSE Physics Past year paper - 2015, Class 12 for NEET Preparation
CBSE Physics Past year paper - 2015, Class 12 Free PDF Download
The CBSE Physics Past year paper - 2015, Class 12 is an invaluable resource that delves deep into the core of the NEET exam.
These study notes are curated by experts and cover all the essential topics and concepts, making your preparation more efficient and effective.
With the help of these notes, you can grasp complex subjects quickly, revise important points easily,
and reinforce your understanding of key concepts. The study notes are presented in a concise and easy-to-understand manner,
allowing you to optimize your learning process. Whether you're looking for best-recommended books, sample papers, study material,
or toppers' notes, this PDF has got you covered. Download the CBSE Physics Past year paper - 2015, Class 12 now and kickstart your journey towards success in the NEET exam.
Importance of CBSE Physics Past year paper - 2015, Class 12
The importance of CBSE Physics Past year paper - 2015, Class 12 cannot be overstated, especially for NEET aspirants.
This document holds the key to success in the NEET exam.
It offers a detailed understanding of the concept, providing invaluable insights into the topic.
By knowing the concepts well in advance, students can plan their preparation effectively.
Utilize this indispensable guide for a well-rounded preparation and achieve your desired results.
CBSE Physics Past year paper - 2015, Class 12 Notes
CBSE Physics Past year paper - 2015, Class 12 Notes offer in-depth insights into the specific topic to help you master it with ease.
This comprehensive document covers all aspects related to CBSE Physics Past year paper - 2015, Class 12.
It includes detailed information about the exam syllabus, recommended books, and study materials for a well-rounded preparation.
Practice papers and question papers enable you to assess your progress effectively.
Additionally, the paper analysis provides valuable tips for tackling the exam strategically.
Access to Toppers' notes gives you an edge in understanding complex concepts.
Whether you're a beginner or aiming for advanced proficiency, CBSE Physics Past year paper - 2015, Class 12 Notes on EduRev are your ultimate resource for success.
CBSE Physics Past year paper - 2015, Class 12 NEET Questions
The "CBSE Physics Past year paper - 2015, Class 12 NEET Questions" guide is a valuable resource for all aspiring students preparing for the
NEET exam. It focuses on providing a wide range of practice questions to help students gauge
their understanding of the exam topics. These questions cover the entire syllabus, ensuring comprehensive preparation.
The guide includes previous years' question papers for students to familiarize themselves with the exam's format and difficulty level.
Additionally, it offers subject-specific question banks, allowing students to focus on weak areas and improve their performance.
Study CBSE Physics Past year paper - 2015, Class 12 on the App
Students of NEET can study CBSE Physics Past year paper - 2015, Class 12 alongwith tests & analysis from the EduRev app,
which will help them while preparing for their exam. Apart from the CBSE Physics Past year paper - 2015, Class 12,
students can also utilize the EduRev App for other study materials such as previous year question papers, syllabus, important questions, etc.
The EduRev App will make your learning easier as you can access it from anywhere you want.
The content of CBSE Physics Past year paper - 2015, Class 12 is prepared as per the latest NEET syllabus.
|
© EduRev
|
Education Revolution
|
Follow Us
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup