2. SECTION – I
Single Correct Answer Type
There are five parts in this question. Four choices are given for each part and one of them is
correct. Indicate you choice of the correct answer for each part in your answer-book by
writing the letter (a), (b), (c) or (d) whichever is appropriate
3. 01 Problem
The length of a simple pendulum is about 100 cm know to an accuracy of 1 mm,
It’s period of oscillation is 2 s determined by measuring the time for 100
oscillations using a clock of 0.1 s resolution. What is the accuracy in the
determined value of g?
a. 0.2%
b. 0.5%
c. 0.1%
d. 2%
4. 02 Problem
Young ‘s modulus of the material of a wire is Y. on pulling the wire by a force F,
the increase in it’s length is x. The potential energy of the stretched wire is:
1
a. 2
Fx
1
b. 2 Yx
c. 1 Fx2
2
d. none of the above
5. 03 Problem
A charge situated at a certain distance along the axes of an electric dipole
experiences a force F. If the distance of the charge from the dipole is doubled,
the force acting on it will become :
a. 2F
b. F/2
c. F/4
d. F/8
6. 04 Problem
Which of the following plots represents the variation of the electric filed with
distance from the centre of a uniformly charged non-conducting sphere of
radius R?
a.
b.
c.
d.
7. 05 Problem
A certain electrical conductor has a square cross-section , 2.0 mm on a side, and
is 121 m long. The resistance between its ends is 0.072 . The resistivity of its
material is equal to
a. 2.4 x 10-6 m
b. 1.2 x 10-6 m
c. 1.2 x 10-8 m
d. 2.4 x 10-8 m
8. 06 Problem
Figure shows three points A,B and C in a region of uniform electric field E . The
line AB is perpendicular and BC is parallel to the field lines. Then which of the
following holds good?
a. VA =VB=VC
b. VA = VB >VC
c. VA =VB >VC
d. VA =VB =VC
Where VA,VB and VC represent the electric potentials at points A,B and C
respectively.
9. 07 Problem
The (x,y,z)coordinates of two points A and B are given respectively as (o,3,-1) and
(-2,6,4).The displacement vector from A to B may be given by:
a. 2ˆ
i 6ˆ
j ˆ
4k
b. i j ˆ
2ˆ 3ˆ 3k
c. i j ˆ
2ˆ 3ˆ 5k
2ˆ
i ˆ
3ˆ 5k
j
d.
10. 08 Problem
In the first second of its flight, rocket ejects of its mass with a velocity of
2400ms-1. The acceleration of the rocket is:
a. 19.6ms-2
b. 30.2ms-2
c. 40ms-2
d. 49.8ms-2
11. 09 Problem
In the given figure the pulley is assumed massless and frictionless. If the friction
force on the object of mass m is f, then its acceleration in terms of the force F will
be equal to:
a. (F-f)/m
F
f /m
b. 2
c. F/m
d. None of these
12. 10 Problem
The equivalent resistance between the points P and Q in the network shown in
the figure is given by:
a. 2.5
b. 7.5
c. 10
d. 12.5
13. 11 Problem
the magnetic field amplitude of an electromagnetic wave is 2 x 10-7 T. It’s
electric field amplitude if the wave is traveling in free space is :
a. 6Vm-1
b. 60Vm-1
10 1
c. Vm
6
d. none of these
14. 12 Problem
A cart is moving horizontally along a straight line with constant speed 30m/s. A
projectile is to be fired from the moving cart in such a way that it will return to
the cart after the cart has moved 80m. at what speed (relative to the cart )must
the projectile be fired ?(Take g=10m/s2):
a. 10 8m / s
b. 10 8m / s
40
c.
3
d. None of these
15. 13 Problem
A boy begins to walk eastward along a street infront of his house, and the graph
in the following figure. His average speed for the whole time interval is equal to
:
a. 8 m/min.
b. 6 m/min
8
c. 3 m/min
d. 2 m/min
16. 14 Problem
What is the potential drop between points A and C in the following circuit ?
Resistances 1 and 2 represent the internal resistances of the respective cells :
a. 1.75 V
b. 2.25 V
5
c. 4 V
d. 4 V
5
17. 15 Problem
The escape velocity of a projectile on the earth’s surface is 11.2 km s-1. A body is
projected out with thrice this speed. The speed of the body far away from the
earth will be :
a. 22.4 km s-1
b. 31.7 km s-1
c. 33.6 km s-1
d. none of the above
18. 16 Problem
A body moves along a circular path of radius 10m and the coefficient of friction
is 0.5 What should be its angular velocity in rad/sec if it is not to slip form the
surface ? (g = 9.8 ms-2)
a. 5
b. 10
c. 0.1
d. 0.7
19. 17 Problem
One end of a string of length l is connected to a particle of mass m and the
other to a small peg on a smooth horizontal table. If the particle moves in a
circle with speed, , the net force on the particle (directed towards the centre) is
:
a. T 2
m
b. T- l
2
c. T + m
l
d. 0
T is the tension in the string .
20. 18 Problem
A body is initially at rest. It undergoes one-dimensional motion with constant
acceleration. The power delivered to it at time t proportional to :
a. t1/2
b. t
c. t3/2
d. t2
21. 19 Problem
In the adjacent figure is shown a closed path P. A long straight conductor carrying
a current I passes through O and perpendicular to the plane of the paper. Then
which of the following hold good ?
a. B dl 0
p
b. B dl 0 I
p
c. B dl 0 I
p
d. None of the above
22. 20 Problem
A long hollow copper tube carries a current I. Then which of the following will be
true ?
a. The magnetic field B will be zero at all points inside the tube
b. The magnetic field B will be zero only at points on the axis of the tube
c. The magnetic field B will be maximum at points on the axis of the tube
d. The magnetic field will be zero at any points outside the tube
23. 21 Problem
PV
The figure below shows the plot of versus P for oxygen gas at two
nT
different temperatures
Read the following statements concerning the above curves :
(i) the dotted line corresponds to the ‘ideal’ gas behaviour
(ii) T1 > T2
PV
(iii) The value of at the point where the curves meet on the y-axis is the
nT
same for all gases.
Which of the above statements is true ?
a. (i) only
b. (i) and (ii) only
c. all the above
d. None of the above
24. 22 Problem
The following figure represents the temperature versus time plot for a given
amount of a substance when heat energy is supplied to it at a fixed rate and at a
constant pressure.
Which part of the above plot represent a phase change ?
a. a to b and e to f
b. b to c and c to d
c. d to e and e to f
d. b to c and d to e
25. 23 Problem
A bar magnet has a coercivity 4 x 103 A. m-1. It is desired to demagnetize it by
inserting it inside a solenoid 12 cm long and having 60 turns. The current
carried by the solenoid should be :
a. 8 A
b. 6 A
c. 4.5 A
d. 2 A
26. 24 Problem
In a series LCR circuit the frequency of a 10 V a.c voltage source is adjusted in such
a fashion that the reactance of the inductor measures 15 and that of the
capacitor 11 . If R = 3 , the potential difference across the series combination of L
and C will be :
a. 8 V
b. 10 V
c. 22 V
d. 52 V
27. 25 Problem
A circuit draws 330 W from a 110 V, 60 Hz a.c. line. The power factor is 0.6 and
the current lags the voltage. The capacitance of a series capacitor that will
result in a power factor of unity is equal to :
a. 31 μF
μF
b. 54
c. 151 μF
d. 201 μF
28. 26 Problem
If the focal length of the lens is 20 cm, what is the distance of the image from the
lens in the following figure ?
a. 5.5 cm
b. 7.5 cm
c. 12.0 cm
d. 20.0 cm
29. 27 Problem
An open U-tube contains mercury. When 11.2 cm of water is poured into one of
the arms of the tube, how high does the mercury rise in the other arm from its
initial level ?
a. 0.56 cm
b. 1.35 cm
c. 0.41 cm
d. 2.32 cm
30. 28 Problem
The change in the entropy of a l mole of an ideal gas which went through an
isothermal process from an initial state (P1, V1, T) to the final state (P2, V2, T) is
equal to :
a. Zero
b. R ln T
V1
c. R ln V2
V2
d. R ln
V1
31. 29 Problem
An unpolarized beam of light is incident on a glass surface at an angle of
incidence equal to the polarizing angle of the glass. Read the following
statements :
(i) the reflected beam is completely polarized
(ii) the reflected beam is partially polarized
(iii) the angle between the reflected and the refracted beams is 900.
Which of the above statements is/are true ?
a. (i) only
b. (ii) only
c. (i ) and (iii)
d. all the statements are correct
32. 30 Problem
The threshold frequency for certain metal is 3.3 x 1014 Hz. If light of frequency 8.2
x 1014 Hz is incident on the metal, the cut-off voltage of the photoelectric current
will be :
a. 4.9 V
b. 3.0 V
c. 2.0 V
d. 1 V
33. 31 Problem
Frequencies higher than 10 MHz were found not being reflected by the
ionosphere on a particular day at a place. The maximum electron density of the
ionosphere on the day was near to :
a. 1.5 x 1010 m-3
b. 1.24 x 1012 m-3
c. 3 x 1012 m-3
d. None of the above
34. 32 Problem
The de-Broglie wavelength of an electron, -particle and a proton all having the
same kinetic energy is respectively given as e , and p
Then which of
the following is not true ?
a. e p
b. p
c. e
p e
d.
35. 33 Problem
What is the disintegration constant of radon if the number of its atoms
diminishes by 18% in 24 hours ?
a. 2.1 x 10-3 s-1
b. 2.1 x 10-4 s-1
c. 2.1 x 10-5 s-1
d. 2.1 x 10-6 s-1
36. 34 Problem
Which of the following statements is true for an n–type semi-conductor ?
a. The donor level lies closely below the bottom of the conduction band.
b. The donor level lies closely above the top of the valence band
c. The donor level lies at the halfway mark of the forbidden energy gap.
d. None of the above
37. 35 Problem
Carbon, silicon and germanium have four valence electrons each. These are
characterized by valence and conduction bands separated by energy band gap
respectively equal to (Eg)C, (Eg)Si and (Eg)Ge, Which of the following statements is
true ?
a. (Eg)C = (Eg)Si = (Eg)Ge
b. (Eg)C > (Eg)Si > (Eg)Ge
c. (Eg)C < (Eg)Ge > (Eg)Si
d. (Eg)Si < (Eg)Ge > (Eg)C
38. 36 Problem
A particle executes SHM of amplitude 25 cm and time period 3 s. What is the
minimum time required for the particle to move between two points 12.5 cm on
either side of the mean position ?
a. 0.5 s
b. 1.0 s
c. 1.5 s
d. 2.0 s
39. 37 Problem
The speed of a wave on a string is 150 m/s when the tension is 120 N. The
percentage increase in the tension in order to raise the wave speed by 20% is :
a. 44%
b. 40%
c. 20%
d. 10%
40. 38 Problem
A straight rod of length L has one of its ends at the origin and the other at x = L. If
the mass per unit length of the rod is given by Ax where A is constant, where is
its mass centre ?
a. L/3
b. L/2
c. 2L/3
d. 3L/4
41. 39 Problem
The image of a small electric bulb fixed on the wall of a room is to be obtained on
the opposite wall 4 m away by means of a large convex lens. The maximum
possible focal length of the lens required for this purpose will be :
a. 0.5 m
b. 1.0 m
c. 1.5 m
d. 2.0 m
42. 40 Problem
The total energy of a satellite moving with an orbital velocity around the earth is
:
1 2
a. m
2
1 2
b. - m
2
2
c. m
3 2
m
d. 2
