Question

71. Which one among the following happens
when a swing rises to a certain height from
its rest position ?
(a) Its potential energy decreases while
kinetic energy increases
(b) Its kinetic energy decreases while
potential energy increases
(c) Both potential and kinetic energy
decrease
(d) Both potential and kinetic energy
increase​

Answer 1

As the swing rises, its kinetic energy is converted to potential energy and as the height increases, PE increases because PE = mgh. And according to law of conservation of energy, total energy E = KE+PE is constant. Hence, we can infer that KE decreases and PE increases.

Answer 2

Answer:

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