Assertion(A): | Stress is the restoring force per unit area of a body. |
Reason(R): | Rubber is more elastic than steel. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Young's modulus for a perfectly plastic body is zero. |
Reason (R): | For a perfectly plastic body, restoring force is zero. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Lead is more elastic than rubber. |
Reason (R): | If the same load is attached to lead and rubber wires of the same cross-sectional area, the strain of lead is very much less than that of rubber. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
A student plots a graph from his readings on the determination of Young modulus of a metal wire but forgets to put the labels (figure). The quantities on X and Y-axes may be respectively,
a. | weight hung and length increased |
b. | stress applied and length increased |
c. | stress applied and strain developed |
d. | length increased and the weight hung |
Choose the correct option:
1. | (a) and (b) |
2. | (b) and (c) |
3. | (a), (b) and (d) |
4. | all of these |
A copper and a steel wire of the same diameter are connected end to end. A deforming force \(F\) is applied to this composite wire which causes a total elongation of \(1\) cm. The two wires will have:
a. | the same stress |
b. | different stress |
c. | the same strain |
d. | different strain |
Choose the correct option:
1. | (a, b) |
2. | (a, d) |
3. | (b, c) |
4. | (c, d) |