Shearing stress causes a change in-
1. Length
2. Breadth
3. Shape
4. Volume
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 strain-stress curves of three wires of different materials are shown in the figure. \(P\), \(Q\) and \(R\) are the elastic limits of the wires. The figure shows that:
1. | Elasticity of wire \(P\) is maximum. |
2. | Elasticity of wire \(Q\) is maximum. |
3. | Tensile strength of \(R\) is maximum. |
4. | None of the above is true. |
The diagram shows a force-extension graph for a rubber band. Consider the following statements
I. It will be easier to compress this rubber than expand it
II. Rubber does not return to its original length after it is stretched
III. The rubber band will get heated if it is stretched and released
Which of these can be deduced from the graph?
1. III only
2. II and III
3. I and III
4. I only
The adjacent graph shows the extension of a wire of length 1m suspended from the top of a roof at one end with a load W connected to the other end. If the cross sectional area of the wire is calculate the young’s modulus of the material of the wire
1.
2.
3.
4.
The diagram shows stress v/s strain curve for the materials A and B. From the curves we infer that
1. A is brittle but B is ductile
2. A is ductile and B is brittle
3. Both A and B are ductile
4. Both A and B are brittle
If the potential energy of a spring is V on stretching it by 2 cm, then its potential energy when it is stretched by 10 cm will be
1. V/25
2. 5V
3. V/5
4. 25V
Two wires of the same diameter of the same material having the length \(l\) and \(2l.\) If the force \(F\) is applied on each, the ratio of the work done in the two wires will be:
1. \(1 : 2 \)
2. \(1 : 4\)
3. \(2 : 1 \)
4. \(1 : 1\)
A \(5~\text{m}\) long wire is fixed to the ceiling. A weight of \(10~\text{kg}\) is hung at the lower end and is \(1~\text{m}\) above the floor. The wire was elongated by \(1~\text{mm}.\) The energy stored in the wire due to stretching is:
1. zero
2. \(0.05~\text J\)
3. \(100~\text J\)
4. \(500~\text J\)
If the force constant of a wire is \(K\), the work done in increasing the length of the wire by \(l\) is:
1. \(\frac{Kl}{2}\)
2. \(Kl\)
3. \(\frac{Kl^2}{2}\)
4. \(Kl^2\)