Class – XI
Revision Worksheet
Chapter-9, 10
1. A cable is replaced by another cable of the same length and material but of
half the diameter.
(a) How does this affect its elongation under a given load?
(b) How many times will be the maximum load it can now support without
exceeding the elastic limit?
2. Define the term strain. Why it has no units and dimensions? What are
different types of strain?
3. Define the term stress. Give its units and dimensions. Describe the different
types of stress.
4. On the basis of stress-strain curves, distinguish between ductile and brittle
materials.
5. Stress strain curve for two wires of material A and B are as shown in figure.
(a) Which material in more ductile?
(b) Which of the two is stronger material?
(c) Which material is more brittle?
6. Why two ships moving in parallel directions close to each other get attracted?
7. What is the net weight of a body when it falls with terminal velocity through a
viscous medium?
8. Explain why, when we try to close a water tap with our fingers, fast jets of water
gush through the openings between our fingers?
9. Derive the ascent formula for rise of liquid in capillary tube. What will happen, if
the length of the capillary tube is smaller than the height to which the liquid rises.
Explain.
10. Explain how a small spherical rigid body attains terminal velocity while falling
through a viscous liquid.
