Dixit Physics

SOLIDS NEET TEST # 1

NEET-UG - Physics
Time Allowed: 3 hours Maximum Marks: 160

1. In solids interatomic forces are [4]

a) both totally repulsive and totally attractive b) totally repulsive

c) totally attractive d) repulsive

2. The property of a body by virtue of which it tends to regain its original size and shape of a body when applied [4]
force is removed, is known as

a) rigidity b) plasticity

c) fluidity d) elasticity
3. The term liquid crystal refers to a state that is intermediate between [4]

a) amorphous liquid and its vapour b) crystalline solid and amorphous liquid

c) crystalline solid and vapour d) a crystal immersed in a liquid

4. To what depth below the surface of the sea should a rubber ball be taken so as to decreases its volume by 0.1 %? [4]
(Take : density of seawater = 1000 kg m-3, bulk modulus of rubber = 9 × 108 Nm-2 and acceleration due to

gravity = 10 ms-2)

a) 9 m b) 18 m

c) 90 m d) 180 m

5. A 4 m long copper wire of cross-sectional area 1.2 cm2 is stretched by a force of 4.8 × 103 N. Young's modulus [4]

for copper is Y = 1.2 × 1011 N/m2. The increase in length of the wire is

a) 0.48 mm b) 0.8 mm

c) 5.36 mm d) 1.32 mm

6. A specimen of oil having an initial volume of 600 cm3 s subjected to a pressure increase of 3.6 × 106 Pa and the [4]
volume is found to decrease by 0.45 cm3 what is the compressibility of the material?

a) 2.3 × 10-10 Pa −1 b) 2.1 × 10-10 Pa−1

c) 1.7 × 10-10 Pa −1 d) 1.9 × 10-10 Pa −1

7. If in a wire of Young's modulus Y, longitudinal strain X is produced, then the value of potential energy stored in [4]
its unit volume will be

a) 2YX2 b) YX2

c) 0.5Y2X d) 0.5YX2

8. Two strips of metal are riveted together at their ends by four rivets, each of diameter 6.0 mm. What is the [4]
maximum tension that can be exerted by the riveted strip if the shearing stress on the rivet is not to exceed 6.9 ×

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 107 Pa? Assume that each rivet is to carry one-quarter of the load:

a) 7.2 × 103 N b) 7.0 × 103 N

c) 7.8 × 103 N d) 6.5 × 103N

9. A and B are two wires. The radius of A is twice that of B. They are stretched by the same load. Then, the stress [4]
on B is

a) four times that on A b) equal to that on A

c) two times that on A d) half that on A

10. If the shear stress exceeds about 4.00 × 108 N/m2, steel ruptures. Determine the shearing force necessary to [4]
shear a steel bolt 1.00 cm in diameter?

a) 3.44 × 104 N b) 3.34 × 104 N

c) 3.14 × 104 N d) 3.24 × 104 N

11. An iron rod of length 2m and cross-sectional area of 50 mm2 is stretched by 0.5 mm, when a mass of 250 kg is [4]
hung from its lower end. Young's modulus of iron rod is

a) 19.6 × 1018 Nm-2 b) 19.6 × 1020 Nm-2

c) 19.6 × 1015 Nm-2 d) 19.6 × 1010 Nm-2

12. For a constant hydraulic stress on an object, the fractional change in the object’s volume ( ) and its bulk [4]
ΔV

modulus (B) are related as:

a) ΔV

V
∝ B b) ΔV

V
∝
1

c) d)
ΔV −2 ΔV 2
∝ B ∝ B
V V

13. A sphere of radius 3 cm is subjected to a pressure of 100 atm. Its volume decreases by 0.3 c.c. What will be its [4]
bulk modulus?

a) 4π × 10 5
b) 4π × 10
8
atm

c) 4π × 10 atm 6
d) 4π × 3 × 10
3
atm
14. Two wires are made of the same material and have the same volume. The first wire has cross-sectional area A [4]
and the second wire has cross-sectional area 3A. If the length of the first wire is increased by Δl on applying a
force F, how much force is needed to stretch the second wire by the same amount?

a) 6 F b) 9 F

c) 4 F d) F

15. A 200-kg load is hung on a wire with a length of 4.00 m, a cross-sectional area of 0.200 × 10−4 m2, and [4]

Young’s modulus of 8.00 × 1010 N/m2. What is its increase in length?

a) 4.70 mm b) 4.90 mm

c) 5.00 mm d) 4.80 mm
16. For a constant hydraulic stress P on an object with bulk modulus (B), the fractional change in the volume of the [4]
object will be
2
a) ( B
) b) B

P
P

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 −
−
c) P

B
d) √
P

17. A cube is subjected to a uniform volume compression. If the side of the cube decreases by 2 % the bulk strain is [4]

a) 0.03 b) 0.02

c) 0.06 d) 0.04
18. If the ratio of lengths, radii and Young’s modulus of steel and brass wires in the figure are a, b and c respectively, [4]
then the corresponding ratio of increase in their lengths would be:

a) 3c

2
b) 3a

2
2ab 2b c

c) d)
2ac 2a c
2
b b

19. A stone is suspended in a tub of water with copper wire. Another stone of equal mass is suspended in kerosene [4]
with equal length of copper wire, then:

a) elongation will be less in the former case b) Young’s modulus is more in the first case

c) elongation will be more in the former case d) Young’s modulus is more in the second case
20. The following four wires are made of the same material. Which of these will have the largest extension, when [4]
the same tension is applied?

a) Length 100 cm and diameter 1 mm b) Length 200 cm and diameter 2 mm

c) Length 300 cm and diameter 3 mm d) Length 50 cm and diameter 0.5 mm

21. A wire of radius r stretched without tension along a straight line is lightly fixed at A and B. What is the tension [4]
in the wire when it is pulled into the shape ACB? (Assume Young’s modulus of the material of the wire to be Y
and d < l)

2 2 2

a) Yd

2
2
b) Y πr l
2
2πr l 2d

2 2 2

c) Y πr d

2
d) Y πr

2 2
2l 2l d

22. When a force is applied on a wire of uniform crosssection area 2 × 106 m-2 and length 6 m, the increase in [4]

length is 1 mm. Energy stored in it will be: (Y = 2 × 1011 Nm-2)

a) 0.023 J b) 0.033 J

c) 0.33 J d) 3.3 J

23. If the shear stress exceeds about 4.00 × 108 N/m2, steel ruptures. Determine the shearing force necessary to [4]

punch a 1.00-cm-diameter hole in a steel plate 0.500 cm thick?

a) 6.28 × 104 N b) 6.18 × 104 N

c) d)

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 5.98 × 104 N 6.08 × 104 N
24. A 12.0-kg mass, fastened to the end of aluminum wire with an unstretched length of 0.50 m, is whirled in a [4]
vertical circle with a constant angular speed of 120 rev/min. The cross-sectional area of the wire is 0.014 cm2.
Calculate the elongation of the wire when the mass is at the lowest point of the path (young modulus of steel =
0.70 × 1011 N/m2)?

a) 0.56 cm b) 0.50 cm

c) 0.54 cm d) 0.52 cm
25. Force constant of a spring (K) is synonymous to: [4]

a) YL

A
b) AL

c) ALY d) YA

26. The diagram shows the change x in length of a thin uniform wire caused by the application of stress F, at two [4]
different temperatures T1 and T2. The variations shown suggest that:

a) Data insufficient b) T1 > T2

c) T1 < T2 d) T1 = T2

27. A nylon rope, 3 cm in diameter, has a breaking strength of 1.5 × 105 N. The breaking strength of a similar rope [4]
of diameter 1.5 cm and same length is

a) 0.75 × 105 N b) 3 × 105 N

c) 0.375 × 105 N d) 6 × 105 N

28. Four identical hollow cylindrical columns of mild steel support a big structure of mass 50,000 kg. The inner and [4]
outer radii of each column are 30 and 60 cm respectively. Assuming the load distribution to be uniform,
calculate the compression strain of each column? Take Young's modulus of steel as 20 × 1010 Pa

a) 7.95 × 10-6 b) 7.1 × 10-6

c) 7.0 × 10-7 d) 7.224 × 10-7

29. For an ideal liquid: [4]

a) bulk modulus is infinite and shear modulus b) bulk modulus is zero and shear modulus is
is zero also zero

c) bulk modulus is infinite and shear modulus d) bulk modulus is zero and shear modulus is
is also infinite infinite

30. The compressibility of water is 4 × 10-5 per unit atmospheric pressure. The decrease in volume of 100 cm3 of [4]
water under a pressure of 100 atmosphere will be

a) 0.4 cm3 b) 0.025 cm3

c) 0.004 cm3 d) 4 × 10-5 cm3

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31. Liquids have no Poisson's ratio, because [4]

a) they have definite shape b) they have no definite shape

c) they have greater volume d) they have lesser density than solid
32. The relation between Y, G, and B is: [4]

a) b)
2 1 1 9 3 1
= + = +
Y 3G 9B Y G B

c) 9

Y
=
1

G
+
3

B
d) 1

Y
=
9

G
+
3

33. A wire is loaded by weights of density 9 g cm-3 and stretched to a length of 98 cm. On immersing the weights in [4]
water, the length shortens by 2.5 mm. The original length of the wire is:

a) 85.75 cm b) 98.75 cm

c) 90.75 cm d) 95.75 cm
34. The Youngs modulus of a wire of length L and radius r is Y. If the length is reduced to and radius is, then [4]
L R

3 3

the Youngs modulus will be:

a) Y

9
b) Y

c) Y

27
d) Y
35. The volume of a wire remains unchanged when the wire is subjected to a certain tension. The Poisson’s ratio of [4]
the material of the wire is

a) 0.4 b) 0.25

c) 0.75 d) 0.5
36. The Poissons ratio of a material is 0.5. If a force is applied to a wire of this material, there is a decrease in the [4]
cross-sectional area by 6%. The percentage increase in the length is:

a) 12% b) 6%

c) 3% d) 11%
37. You hang a flood lamp from the end of vertical steel wire. The flood lamp stretches the wire 0.18 mm and the [4]
stress is proportional to the strain. How much would it have stretched if the wire had the same length but twice
the diameter?

a) 0.075 mm b) 0.045 mm

c) 0.055 mm d) 0.065 mm
38. In designing a beam for its use to support a load, the depression at centre (where, Y is Young's modulus) is [4]
proportional to

a) 1
2
b) 1

Y
Y

c) Y2 d) Y

39. Two wires of the same material and same length but diameters in the ratio 1 : 2 are stretched by the same force. [4]
The potential energy per unit volume of the two wires will be in the ratio:

a) 4 : 1 b) 16 : 1

c) 2 : 1 d) 1 : 2

40. A force of 6 × 106Nm-2 is required for breaking a material. The density ρ of the material is 3 × 103kg m-3. If [4]

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the wire is to break under its own weight, the length of the wire made of that material should be (Taking g =

10ms-2):

a) 200 m b) 2000 m

c) 20 m d) 100 m

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