The temperature of the wire is doubled. Young's modulus of elasticity:
1. | will also double. |
2. | will become four times. |
3. | will remain the same. |
4. | will decrease. |
Consider two cylindrical rods of identical dimensions, one of rubber and the other of steel. Both the rods are fixed rigidly at one end of the roof. A mass M is attached to each of the free ends at the centre of the rods.
1. | Both the rods will elongate but there shall be no perceptible change in shape. |
2. | The steel rod will elongate and change shape but the rubber rod will only elongate. |
3. | The steel rod will elongate without any perceptible change in shape but the rubber rod will elongate and the shape of the bottom edge will change to an ellipse. |
4. | The steel rod will elongate without any perceptible change in shape but the rubber rod will elongate with the shape of the bottom edge tapered to a tip at the centre. |
A rod of length l and negligible mass is suspended at its two ends by two wires of steel (wire A) and aluminium (wire B) of equal lengths (figure). The cross-sectional areas of wires A and B are respectively. ()
a. | Mass m should be suspended close to wire A to have equal stresses in both wires. |
b. | Mass m should be suspended close to B to have equal stresses in both wires. |
c. | Mass m should be suspended in the middle of the wires to have equal stresses in both wires. |
d. | Mass m should be suspended close to wire A to have equal strain in both wires. |
The correct statements are:
1. (b, c)
2. (a, d)
3. (b, d)
4. (c, d)