Class 12 Sample Paper 2022 Solution Physics Term 1

Practice paper term 1
Class xii
Marking Scheme
Physics
Section A
Q. No. Correct Hint/main points
option
1 a Decreases K times

2 d no work is done

3 a 25 x 10-2 J

U= (1/2)CV2
= (1/2)(50 x 10-6)x100x100
= 25x10-2 J

4 c 1:1

BA= µ0 I / 2R and
BB = µ0 (2I) / 2 (2R)
= µ0 I / 2R
Therefore BA / BB = 1:1

5 b Very weak temperature dependent
resistivity

6 a 3.1 x 10-4 T

B= µo NI/2r = 4𝜋 x 10-7x 100 x
0.40/(2 x 0.08) = 3.1 x 10-4 T

7 a tan-1 1.7272

tan ε =Bv/BH = 0.38/0.22
=1.7272; ε =tan-1 1.7272

8 a Scalar Quantity

9 a Gauss’s law

10 c 1.6 x 10-19 C

11 d E axial= 1/4πε0 (2p/r3)

12 d All of the above

13 a Parallel planes perpendicular to
the direction of electric field.

14 c Q∝V

15 b The magnetic field lines of a
magnet do not form continuous
closed loops.

16 a m = NIA

17 d e = - dø/dt

18 b
(i ) b c d a b ; (ii) b a c b

19 d
6.28 x 10-5 V

Solution:
e = Bvl =B(1/2rw)l=B ½ r (2 π f )l
=0.4x10-4x 0.5 x
(22/7)x(2rps)x0.5
=6.28 x10-5 volts
here v = av. linear velocity = ½( velocity at
rim+ velocity at axil)
= ½ (rw+0)
=1/2 r w

20 a
Alternating voltage

21 a
Current I lags behind the voltage
by π/2

22 c
L dI/dt + IR+ q/C = V

23 d
Relates with L-C-R circuit.

24 b
I rms = Im / √2

25 a
Transformer

Section B
26 c
6 x 10-3 N

Hint:Use formula F = k q1q2/r2

27 b
+1.6 C

Hint: use q=ne

28 a
Increases

29 a
4 µF

As circuit is satisfying
Wheatstone bridge condition
C Ac = (4x4)/(4+4) +
(4x4)/(4+4)
=2 + 2 = 4 µF

30 a
Decreases

Explanation: The net field
between the plates decreases as
an electric field is induced in the
opposite direction of the applied
field.

31 c
4 x 103 V/m

E =V/d =12/3x 10-3 = 4 x 103 v/m

32 b
30 A
Imax = E/r+R = 12/0.4+0= 30 A
here R=0 for max. Current

33 d
2.25 V

Use E2/E1= l2/l1

34 b
gets doubled

Hint; Use Drift velovity formula
Vd=eET/m

35 a
(i) CD; (ii) AB

36 c resistance of 60 watt bulb is
greater than resistance of 100
watt bulb

Hint: Use P= V2/R

37 c
Both a and b

38 a
RA < Rg < Rv

39 d
0.96 Nm

40 b Clockwise
41 a
Maximum in situation (i)

42 c
Four times

Hint; L=µ0 n2 A I; L ∝ n2

43 d
Pure resistor

44 d
Energy

45 d A is false and R is also false

Explanation: A stationary charge
produces only an electric field .A
moving charge is associated both
with electric and magnetic field
46 a
Both A and R are true and R is

the correct explanation of A.
Explanation:
A stationary charge produces only
an electric field .A moving charge
is associated both with electric
and magnetic field.

47 a
Both A and R are true and R is

the correct explanation of A.

48 a
Both A and R are true and R is

the correct explanation of A.

Explanation: Repulsion between
opposite pairs increase area
enclosed by the irregular loop.

49 a Both A and R are true and R is
the correct explanation of A.

hint: As T=2π m/qB

therefore T ∝ m/q

50 d
Zero

51 d 2mC;

hint: torque =P E sin 300
4 =q x 2a E sin 300
q=2mC

52 a
Zero

53 d
Unknown resistance

54 c
Meter bridge

55 d Galvanometer