Chapter 30 : Work, Power and Energy 621
(b) no force acts on the body, but displacement takes place,
(c) either (a) or (b)- The rate of doing some work is power.
(a) True (b) False- One watt is equal to
(a) 0.1 J/s (b) 1 J/s
(c) 10 J/s (d) 100 J/s- The units of energy and work done are the same.
(a) Agree (b) Disagree- The kinetic energy of a body of mass (m) and velocity (v) is equal to
(a) mv (b)
2mv
(c)22mv
(d)22mv- The potential energy of a mass (m) kg raised through a height (h) metres is
(a) mh newtons (b) gh newtons
(c) mgh newtons (d) none of theseANSWERS
- (b) 2. (c) 3. (a) 4. (b) 5. (a) 6. (d) 7. (c)
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