The Young's modulus of a wire of length 'L' and radius 'r' is 'Y'. If length is reduced to L/2 and radius r/2, then Young's modulus will be
1. Y/2
2. Y
3. 2Y
4. 4Y
Three wires \(A,B,C\) made of the same material and radius have different lengths. The graphs in the figure show the elongation-load variation. The longest wire is:
1. \(A\)
2. \(B\)
3. \(C\)
4. All of the above
The breaking stress of a wire depends upon:
1. | material of the wire. |
2. | length of the wire. |
3. | radius of the wire. |
4. | shape of the cross-section. |
The bulk modulus of a spherical object is \(B\). If it is subjected to uniform pressure \(P\), the fractional decrease in radius will be:
1. \(\frac{P}{B}\)
2. \(\frac{B}{3P}\)
3. \(\frac{3P}{B}\)
4. \(\frac{P}{3B}\)
Copper of fixed volume V is drawn into a wire of length l. When this wire is subjected to a constant force F, the extension produced in the wire is Δl. Which of the following graphs is a straight line?
(1) Δl versues 1/l
(2) Δl versus l2
(3) Δl versus 1/l2
(4) Δl versus l
When a certain weight is suspended from a long uniform wire, its length increases by one cm. If the same weight is suspended from another wire of the same material and length but having a diameter half of the first one, then the increase in length will be -
1. 0.5 cm
2. 2 cm
3. 4 cm
4. 8 cm
A force \(F\) is needed to break a copper wire having radius \(R.\) The force needed to break a copper wire of radius \(2R\) will be:
1. | \(F/2\) | 2. | \(2F\) |
3. | \(4F\) | 4. | \(F/4\) |
A and B are two wires of same material. The radius of A is twice that of B. They are stretched by the same load. Then the stress on B is
1. Equal to that on A
2. Four times that on A
3. Two times that on A
4. Half that on A
If the length of a wire is reduced to half, then it can hold the ......... load
1. Half
2. Same
3. Double
4. One fourth
Two wires of copper having length in the ratio of \(4:1\) and radii ratio of \(1:4\) are stretched by the same force. The ratio of longitudinal strain in the two will be:
1. | \(1:16\) | 2. | \(16:1\) |
3. | \(1:64\) | 4. | \(64:1\) |