To break a wire, a force of is required. If the density of the material is , then the length of the wire which will break by its own weight will be:
1. 34 m
2. 30 m
3. 300 m
4. 3 m
The bulk modulus of water is . The increase in pressure required to decrease the volume of water sample by \(0.1\)% is:
1. \(4 \times 10^6 \mathrm{~N} / \mathrm{m}^2 \)
2. \(2 \times 10^{\mathrm{6}}~ \mathrm{N} / \mathrm{m}^2 \)
3. \(2 \times 10^{\mathrm{8}}~ \mathrm{N} / \mathrm{m}^2 \)
4. \(8 \times 10^{\mathrm{6}}~ \mathrm{N} / \mathrm{m}^2 \)
One end of a 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 A is the area of cross-section of the wire , the stress in the wire at a height 3L/4 from its lower end is:
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2.
3.
4.
The length of elastic string, obeying Hooke's law is metres when the tension is 4N, and metres when the tension is 5N. The length in metres when the tension is 0 N will be:
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2.
3.
4.
Two wires are made of the same material and have the same volume. The first wire has a cross-sectional area \(A\) and the second wire has a cross-sectional area \(3A\). If the length of the first wire is increased by \(\Delta l\) on applying a force \(F\), how much force is needed to stretch the second wire by the same amount?
1. | \(9F\) | 2. | \(6F\) |
3. | \(4F\) | 4. | \(F\) |
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 \(\Delta l.\) Which of the following graphs is a straight line?
1. \(\Delta l ~\text{vs}~\frac{1}{l}\)
2. \(\Delta l ~\text{vs}~l^2\)
3. \(\Delta l ~\text{vs}~\frac{1}{l^2}\)
4. \(\Delta l ~\text{vs}~l\)
Overall changes in volume and radius of a uniform cylindrical steel wire are 0.2% and 0.002% respectively when subjected to some suitable force. Longitudinal tensile stress acting on the wire is: ( )
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3.
4. 3.9
A uniform cylinder rod of length L, cross-sectional area A and Young's modulus Y is acted upon by the forces, as shown in the figure. The elongation of the rod is:
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2.
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4.
The density of metal at normal pressure is . lts density when it is subjected to an excess pressure P is '. lf B is the bulk modulus of the metal, the ratio is:
1. \(\frac{1}{1-\frac{p}{B}} \)
2. \(1+\frac{B}{P} \)
3. \(\frac{1}{1-\frac{B}{P}} \)
4. \(2+\frac{P}{B}\)
The bulk modulus of rubber is . To what depth a rubber ball be taken in a lake so that its volume is decreased by 0.1%?
1. | 25 m | 2. | 100 m |
3. | 200 m | 4. | 500 m |