Longitudinal Stress

Q. The length of a metal wire is $l_1$ when the tension in it is $T_1$ and is $l_2$ when the tension is $T_2$. The natural length of the wire is

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4. 

Q.

The extension in a string obeying Hooke's law is x. The speed of a transverse wave in a stretched string is v. If the extension in the string is increased to 1.5x, the speed of the wave will be

1. 0.61 v

2. 1.22 v

3. 1.50 v

4. 0.75 v

Q.

A rope 1 cm in diameter breaks if the tension in it exceeds 500N. The maximum tension that may be given to a similar rope of diameter 2 cm is?

1. 500 N

2. 250 N

3. 1000 N

4. 2000 N

Q. A wire elongates by 2 mm when a load W is hanged from it. If this wire goes over a pulley and two weightsW each are hung at the two ends then elongation in the wire will be(2) 0.5 mm(3) 2 mm(4) 4 mm

Q. The coefficient of linear expansion of brass and steel are ${\alpha }_1$ and ${\alpha }_2$. If we take a brass rod of length $L_1$ and steel rod of length $L_2$ at $0^{\circ }C$, their difference in length $(L_2-L_1)$ will remain the same at any temperature if

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2. 
3. 
4. 

Q. A 5 m long aluminium wire $(Y=7\times {10}^{10}N/m^2)$ of diameter 3 mm supports a 40 kg mass. In order to have the same elongation in a copper wire $(Y=12\times {10}^{10}N/m^2)$ of the same length under the same weight, the diameter should now be, in mm

1. 1.75
2. 2.3
3. 2
4. 5

Q. A circular wire frame fo radius R is dipped in soap solution of surface tension s When it is taken out, a thin soapfilm is formed inside the frame. Find the force on the frame. 26. (B) 2R (D) 8ToR

Q. The length of an elastic string is x metres when the tension is 8 newton, and y metres when the tension is 10 newton. The length in metres when the tension is 18 newton is ?

Q. Two strings A and B are fixed at both ends. String A has twice the length, twice the diameter twice the tension and twice the density of string B. The overtone of A that will be in unison with fundamental frequency of B is

Q. if the strain in a wire is not more than 1/1000 and Y = 2 * 10^11 N/m^2, Diameter of wire is 1 mm. The maximum weight hung from the wire is

Q. Which of the following quantities has the same unit as pressure?

1. Strain
2. Stress
3. Momentum
4. Torque

Q.

A beaker of circular cross section of radius 4 cm is filled with mercury up to a height of 10 cm. find the force exerted by the mercury on the bottom of the beaker. The atmospheric pressure = ${10}^{5}N{m}^{-2}$. Density of mercury = $13600kg{m}^{-3}$. Take $g=10m{s}^{-2}$.

1. 571 N

2. 674 N

3. 486 N

4. 544 N

Q. A rod of length 4 m is suspended from two wiresas shown in figure. One of them is made of steeland other of copper of cross-sectional area 10-2m2and 4 x 10-2 m2. Find distance x if equal stress isexperienced by both the wires (Yand Ycopper=2x 1011 N/m2Steel1.1 x 1011 N/m2SteelCopperW(2) 3.5 m(1) 2 m(4) 3 m(3) 3.2 m

Q. Q. A copper wire and steel wire of the same diameter and length are joined end to end and a force is applied which stretches their combined length by 1 cm. then the wires will have a\rbrack same stress & strain b\rbrack different stress & strain c\rbrack same stress but different strain d\rbrack same strain but different stress

Q. which one is dimension less physical quantity velocity gradient, force gradient, stress and angle

Q. A two metre long rod is suspended with the help of two wires of equal length. One wire is of steel and its cross-sectional area is $0.1c{m}^2$ and another wire is of brass and its cross-sectional area is $0.2c{m}^2$. If a load W is suspended from the rod and stress produced in both the wires is same then the ratio of tensions in them will be

1. Will depend on the position of W
2. 
3. 
4. 

Q. A steel cable with a radius of 1.5 cm supports a chairlift at a ski area. If the maximum stress is not to exceed 10⁸ N m¯², what is the maximum load the cable can support ?

Q.

Three physical quantity having dimensions [ M L^-1 T^-2] are.

1. Stress, pressure, work

2. Stress, pressure, coefficient of elasticity

3. Stress, pressure, torque

4. Stress, pressure, density

Q. A steel wire of original length 1 m and cross-sectional area 4.00 mm2 is clamped at the two ends so that it lies horizontally and without tension. If a load of 2:16 kg is suspended from the middle point of the wire, what would be its vertical depression?

Q.

Two blocks of masses 1 kg and 2 kg are connected by a metal wire going over a smooth pulley as shown in figure. The breaking stress of the metal is $2\times {10}^{9}N{m}^{-2}$. What should be the minimum radius of the wire used if it is not to break? Take $g=10m{s}^{-2}$.

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2. 

3. 

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Q. Modulus of elasticity of a material does not depend upon

1. impurities mixed
2. stress
3. nature of material
4. temperature

Q. Q 14/15 If the tension on a wire is removed at once, then 1. tempwrature reduces 2.temperature remain cons†an t 3.temperature increases 4.it will brea

Q. a steel wire is 1 m long and 1 mm2 in area of cross-section. If it takes 200 N to stretch this wire by 1mm, how much force will be required to stretch a wireof the same material as well as diameter from its normal length of 10 m to a length of 1002 cm?(1) 1000 (2) 200 N(4) 2000 N(3) 400 N

Q.

Dimensional formula of stress is same as that of

1. pressure

2. strain

3. impulse

4. force

Q. 98.what is the dimensional formula for stress.?

Q. Q. A wire of length L hold a maximum load W. The length of wire is then reduced to half. how muchload it can hold

Q. A 5m long aluminium wire (Y=7×10^{10} N/m^{-2} )of diameter 3mm supports a 40Kg mass in order to have the same elongation in the copper wire (Y=12×10^{10} N/m^{-2}) of the same length under the same weight the diameter should now be (in mm)

Q. one end of uniform wire of length L and of weight W is attached rigidly to a point in the roof and a weight W1 is suspended from its lower end.if s is the area of cross-section of the wire, the stress in the wire at a height (L/4) from its lower end is

Q.

Two blocks of masses 1 kg and 2 kg are connected by a metal wire going over a smooth pulley as shown in figure. The breaking stress of the metal is $2\times {10}^{9}N{m}^{-2}$. What should be the minimum radius of the wire used if it is not to break? Take $g=10m{s}^{-2}$.

1. 

2. 

3. 

4. 

Q. length of a wire is increased by 1mm on the application of a given load .if same load is applied to another wire of same material but of length and radius twice that of the first then increased in its length will be