EASY

Earn 100

One end of a uniform bar of weight $W_{1}$ is suspended from the roof and a weight $W_{2}$ is suspended from the other end. The area of cross-section is $A$ . What is the stress at the midpoint ?

50% studentsanswered this correctly

Important Questions on Elasticity

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A submarine experiences a pressure of

5.05 \times 10^{6} P a

at a depth of

d_{1}

in a sea. When it goes further to a depth of

d_{2}

, it experiences a pressure of

8.08 \times 10^{6} P a

. Then

d_{2} - d_{1}

is approximately (density of water

= 10^{3} k g / m^{3}

and acceleration due to gravity

= 10 m s^{- 2}

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

Consider a water jar of radius R that has water filled up to height H and is kept on a stand of height h (see figure). Through a hole of radius r

(r < < R)

at its bottom, the water leaks out and the stream of water coming down towards the ground has a shape like a funnel as shown in the figure. If the radius of the cross-section of water stream when it hits the ground is x. Then:

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A steel wire having a radius of

2.0 m m

, carrying a load of

4 k g,

is hanging from a ceiling. Given that

g = 3.1 π m s^{- 2},

what will be the tensile stress that would be developed in the wire?

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

Speed of a transverse wave on a straight wire (mass

6.0 g,

length

60 c m

and area of cross-section

1.0 m m^{2}

90 {m s}^{- 1}

. If the Young's modulus of wire is

16 \times 10^{11} N m^{- 2}

, the extension of wire over its natural length is:

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

The following observations were taken for determining surface tension

T

of water by capillary method:

diameter of capillary,

D = 1.25 \times 10^{- 2} m

rise of water,

h = 1.45 \times 10^{- 2} m

Using

g = 9.80 m s^{- 2}

and the simplified relation

T = \frac{r h g}{2} \times 10^{3} N m^{- 1}

the possible error in surface tension is closest to:

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

Which one of the following statement is correct?

HARD

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

0.27 g

of a long chain fatty acid was dissolved in

100 {c m}^{3}

of hexane.

10 m L

of this solution was added dropwise to the surface of water in a round watch glass. Hexane evaporates and a monolayer is formed. The distance from edge to centre of the watch glass is

10 c m

. What is the height of the monolayer?
[Density of fatty acid

= 0.9 g c m^{- 3}; π = 3]

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A metallic rod breaks when strain produced is

0.2 %

. Young's modulus of the material of the rod is

7 \times 10^{9} N m^{- 2}

. What should be its area of cross-section to support a load of

10^{4} N

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A man grows into a giant such that his linear dimensions increase by a factor of

9 .

Assuming that his density remains same, the stress in the leg will change by a factor of:

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

When one end of the capillary is dipped in water, the height of the water column is

h

. The upward force of

105 dyne

due to surface tension is balanced by the force due to the weight of the water column. The inner circumference of the capillary is
(Surface tension of water

= 7 \times 10^{- 2} N m^{- 1})

HARD

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

Consider a solid sphere of radius

R

and mass density

ρ (r) = ρ_{0} (1 - \frac{r^{2}}{R^{2}}), 0 < r \leq R .

The minimum density of a liquid in which it will float is:

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A particle of mass

1 kg

is moving in SHM with a path length of

0.01 m

and frequency of

50 Hz

. The maximum force in newton, acting on the particle is

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A small spherical droplet of density

d

is floating exactly half immersed in a liquid of density

ρ

and surface tension

T .

The radius of the droplet is (take note that the surface tension applies an upward force on the droplet):

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

In an experiment, brass and steel wires of length

1 m

each with areas of cross section

1 m m^{2}

are used. The wires are connected in series and one end of the combined wire is connected to a rigid support and other end is subjected to elongation. The stress required to produce a net elongation of

0.2 m m

is,
[Given, the Young's Modulus for steel and brass are, respectively,

120 \times 10^{9} N / m^{2}

and

60 \times 10^{9} N / m^{2}

]

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

An aluminium sphere is dipped into water. Which of the following is true?

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

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 on

B

MEDIUM

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A fluid is flowing through a horizontal pipe of varying cross-section, with

v {ms}^{- 1}

at a point where the pressure is

P

Pascal. At another point where pressure

\frac{P}{2}

Pascal its speed is

V {ms}^{- 1}

. If the density of the fluid is

ρ kg - m^{- 3}

and the flow is streamline, then

V

is equal to

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

One end of a horizontal thick copper wire of length

2 L

and radius

2 R

is welded to an end of another horizontal thin copper wire of length

L

and radius

R

. When the arrangement stretched by applying forces at two ends, the ratio of the elongation in the thin wire to that in the thick wire is

EASY

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

A rectangular film of liquid is extended from

(4 cm \times 2 cm)

(5 cm \times 4 cm)

. If the work done is

3 \times 10^{- 4} J

, the value of the surface tension of the liquid is

HARD

Physics>Mechanics>Elasticity>Deformation and Elastic Behaviour of Solids

Assume that a drop of a liquid evaporates by a decrease in its surface energy so that its temperature remains unchanged. The minimum radius of the drop for this to be possible is. (The surface tension is

T

, the density of the liquid is

ρ

and

L

is its latent heat of vaporisation.)

One end of a uniform bar of weight W1 is suspended from the roof and a weight W2 is suspended from the other end. The area of cross-section is A. What is the stress at the midpoint ?

Important Questions on Elasticity

Learn and Prepare for any exam you want !

One end of a uniform bar of weight $W_{1}$ is suspended from the roof and a weight $W_{2}$ is suspended from the other end. The area of cross-section is $A$ . What is the stress at the midpoint ?