Poisson's Effect

Q. Which is correct relation. ($\sigma$ is Poisson's Ratio, Y is the young's Modulus)

1. Y < σ
2. σ = +1
3. Y = σ
4. Y > σ

Q.

Repeated observations in an experiment gave the values 1.29, 1.33, 1.34, 1.35, 1.32, 1.36, 1.30 and 1.33. Find the relative error.

1. 0.025

2. 0

3. 0.0175

4. 0.015

Q. Two wires of the same material and length are stretched by the same force. Their masses are in the ratio 3:2. Their elongations are in the ratio

1. 3 : 2
2. 9 : 4
3. 4 : 9
4. 2 : 3

Q.

One end of a nylon rope of length 4.5 m and diameter 6 mm is fixed to a tree-limb. A monkey weighing 100 N jumps to catch the free end and stays there. Find the elongation of the rope and the corresponding change in the diameter. Young modulus of nylon = 4.8 x 10¹¹ N m^-2 and Poisson ratio of nylon = 0.2.

1. 3.3 x 10^-6 m, 8.8 x 10^-9 m

2. 3.3 x 10^-5 m, 8.8 x 10^-10 m

3. 3.3 x 10^-5 m, 8.8 x 10^-9 m

4. 3.3 x 10^-6 m, 8.8 x 10^-10 m

Q. If the Poisson's ratio for a metal is 0.3, it means that

1. Longitudinal strain is 0.3 times the lateral strain
2. Lateral strain is 0.3 times the longitudinal strain
3. Lateral strain is smaller than the longitudinal strain
4. Longitudinal strain is smaller than the lateral strain

Q. The Poisson's ratio cannot have the value

1. 0.7
2. 0.2
3. 0.1
4. 0.5