Mechanical Properties of Solids
1. Force constant of a spring (K) is Which of these can be deduced from the
synonymous to :- graph:
(1) III only (2) II and III
(3) I and III (4) I only
6. The length of a spring is when a force
of 4N is applied on it and the length is
2. Length of a spring of force constant k in its when 5 N force is applied. Then the length
unscratched condition is l. The spring is of spring when 9 N force is applied is
cut into two parts which have their (1)5 – 4 (2) –
unscratched lengths in the ratio l1 : l2 = q :1 (3) 5 – 4 (4) 9 ( – )
. Force constants of the two parts k1 and k2 7. The pressure of a medium is changed from
are then 1.01 × 105 Pa to 1.165 × 105 Pa to change
its volume by 10% keeping the
temperature constant. The bulk modulus
of the medium is :
(1) 204.8 × 105 Pa (2) 102.4 × 105 Pa
(3) 15.5 × 105 Pa (4) 1.55 × 105 Pa
3. A wire fixed at the upper end stretches by 8. Which of the following will be if Y =
length by applying a force F. The work 2.4
done in stretching is :- (1) –1 (2) 0. 2
F (3) 0. 1 (4) –0.28
(1) (2) F
2
9. A car moves from X to Y with a uniform
F speed vu and returns to Y with a uniform
(3) 2F (4)
2 speed vd. The average speed for this round
4. A uniform rod of mass m, length L, area of trip is :-
cross-section A and Young's modulus Y
hangs from the ceiling. Its elongation
under its own weight will be
10. The length of a rubber cord is 1 metre
(when the tension is 4 N) and 2 metre
(when the tension is 6 N) respectively. The
5. The diagram shows a force-extension length 3 (When the tension is 9 N) is :-
graph for a rubber band. Consider the
following statements:-
(1) (2.5 2 – 1.5 1 )m
(2) (6 2 – 1.5 1 )m
(3) (3 1 –2 2 )m
(I) It will be easier to compress this rubber (4) (3.5 2 – 2.5 1 )m
than expand it
(II) Rubber does not return to its original 11. The mean distance between the atoms of
length after it is stretched iron is 3 × 10–10 m and inter atomic force
(III) The rubber band will get heated if it is constant for iron is 7 N/m. The Young's
stretched and released modulus of elasticity for iron is :
, (3) YB = 3YA (4) YA = 3YB
12. If 'S' is stress and 'Y' is Young's modulus 17. The potential energy U between the atoms
of material of a wire, the energy stored in in a diatomic molecule as a function of the
the wire per unit volume is :- distance x between the atoms is shown in
figure. The atoms
13. A wire of length L and cross-sectional area
A is made of a material of Young's
modulus Y. The work done in stretching
the wire by an amount x is given by
(1) Attract each other when x is between A
14. Copper of fixed volume 'V' is drawn into and B
wire of length 'l'. When this wire is
(2) Attract each other when x is between B
subjected to a constant force 'F', the
extension produced in the wire is ' l'. and C
Which of the following graphs is a straight
(3) Attract each other when x is at B
line?
(4) Repel each other when x is at B
18. A wire of length l, area of cross-section A
and Young's modulus of elasticity Y is
suspended from the proof of a building. A
15. A rod is fixed between two points at 20°C.
block of mass m is attached at lower end of
The coefficient of linear expansion of
the wire. If the block is displacement from
material of rod is 1.1 10–5/°C and
its mean position and then released the
Young's modulus is 1.2 1011 N/m2. Find
block starts oscillation. Time period of
the stress developed in the rod if
these oscillations will be :-
temperature of rod becomes 10°C :
(1) 1.32 107 N/m2 (2) 1.10 1015 N/m2
(3) 1.32 108 N/m2 (4) 1.10 106 N/m2
16. The stress versus strain graphs for wires of
two materials A and B are as shown in the
figure. If YA and YB are the Young's
Al AY
modulus of the materials, then :- (1) 2 (2) 2
mY ml
ml m
(3) 2 (4) 2
YA YAl
19. A copper solid cube of 60 mm side is
subjected to a pressure of 2.5 × 107 Pa. If
the bulk modulus of copper is 1.25 ×
1011N/m2, the change in the volume of
(1) YB = 2YA (2) YA = YB cube is -
1. Force constant of a spring (K) is Which of these can be deduced from the
synonymous to :- graph:
(1) III only (2) II and III
(3) I and III (4) I only
6. The length of a spring is when a force
of 4N is applied on it and the length is
2. Length of a spring of force constant k in its when 5 N force is applied. Then the length
unscratched condition is l. The spring is of spring when 9 N force is applied is
cut into two parts which have their (1)5 – 4 (2) –
unscratched lengths in the ratio l1 : l2 = q :1 (3) 5 – 4 (4) 9 ( – )
. Force constants of the two parts k1 and k2 7. The pressure of a medium is changed from
are then 1.01 × 105 Pa to 1.165 × 105 Pa to change
its volume by 10% keeping the
temperature constant. The bulk modulus
of the medium is :
(1) 204.8 × 105 Pa (2) 102.4 × 105 Pa
(3) 15.5 × 105 Pa (4) 1.55 × 105 Pa
3. A wire fixed at the upper end stretches by 8. Which of the following will be if Y =
length by applying a force F. The work 2.4
done in stretching is :- (1) –1 (2) 0. 2
F (3) 0. 1 (4) –0.28
(1) (2) F
2
9. A car moves from X to Y with a uniform
F speed vu and returns to Y with a uniform
(3) 2F (4)
2 speed vd. The average speed for this round
4. A uniform rod of mass m, length L, area of trip is :-
cross-section A and Young's modulus Y
hangs from the ceiling. Its elongation
under its own weight will be
10. The length of a rubber cord is 1 metre
(when the tension is 4 N) and 2 metre
(when the tension is 6 N) respectively. The
5. The diagram shows a force-extension length 3 (When the tension is 9 N) is :-
graph for a rubber band. Consider the
following statements:-
(1) (2.5 2 – 1.5 1 )m
(2) (6 2 – 1.5 1 )m
(3) (3 1 –2 2 )m
(I) It will be easier to compress this rubber (4) (3.5 2 – 2.5 1 )m
than expand it
(II) Rubber does not return to its original 11. The mean distance between the atoms of
length after it is stretched iron is 3 × 10–10 m and inter atomic force
(III) The rubber band will get heated if it is constant for iron is 7 N/m. The Young's
stretched and released modulus of elasticity for iron is :
, (3) YB = 3YA (4) YA = 3YB
12. If 'S' is stress and 'Y' is Young's modulus 17. The potential energy U between the atoms
of material of a wire, the energy stored in in a diatomic molecule as a function of the
the wire per unit volume is :- distance x between the atoms is shown in
figure. The atoms
13. A wire of length L and cross-sectional area
A is made of a material of Young's
modulus Y. The work done in stretching
the wire by an amount x is given by
(1) Attract each other when x is between A
14. Copper of fixed volume 'V' is drawn into and B
wire of length 'l'. When this wire is
(2) Attract each other when x is between B
subjected to a constant force 'F', the
extension produced in the wire is ' l'. and C
Which of the following graphs is a straight
(3) Attract each other when x is at B
line?
(4) Repel each other when x is at B
18. A wire of length l, area of cross-section A
and Young's modulus of elasticity Y is
suspended from the proof of a building. A
15. A rod is fixed between two points at 20°C.
block of mass m is attached at lower end of
The coefficient of linear expansion of
the wire. If the block is displacement from
material of rod is 1.1 10–5/°C and
its mean position and then released the
Young's modulus is 1.2 1011 N/m2. Find
block starts oscillation. Time period of
the stress developed in the rod if
these oscillations will be :-
temperature of rod becomes 10°C :
(1) 1.32 107 N/m2 (2) 1.10 1015 N/m2
(3) 1.32 108 N/m2 (4) 1.10 106 N/m2
16. The stress versus strain graphs for wires of
two materials A and B are as shown in the
figure. If YA and YB are the Young's
Al AY
modulus of the materials, then :- (1) 2 (2) 2
mY ml
ml m
(3) 2 (4) 2
YA YAl
19. A copper solid cube of 60 mm side is
subjected to a pressure of 2.5 × 107 Pa. If
the bulk modulus of copper is 1.25 ×
1011N/m2, the change in the volume of
(1) YB = 2YA (2) YA = YB cube is -
