ICSE Class 8 Physics Question 2 of 25

Energy — Question 1

Back to all questions
1
Question

Question 3

Fill in the blanks:

(a) Work is said to be done by a force only when ............... .

(b) Work done = Force x ............... .

(c) The energy of a body is its capacity to do ............... .

(d) The S.I. unit of energy is ............... .

(e) The potential energy of a body is due to its ............... and kinetic energy of a body is due to its ............... .

(f) Gravitational potential energy U = mass x force of gravity on unit mass x ............... .

(g) Kinetic energy = 12\dfrac{\text{1}}{\text{2}} x mass x ............... .

(h) Power P = ............... / time taken.

(i) The S.I. unit of power is ............... .

(j) 1 H.P. = ............... W.

Answer

(a) Work is said to be done by a force only when the body moves.

(b) Work done = Force x distance moved in the direction of force.

(c) The energy of a body is its capacity to do work.

(d) The S.I. unit of energy is joule .

(e) The potential energy of a body is due to its state of rest or position and kinetic energy of a body is due to its state of motion.

(f) Gravitational potential energy U = mass x force of gravity on unit mass x vertical height.

(g) Kinetic energy = 12\dfrac{\text{1}}{\text{2}} x mass x (speed)2.

(h) Power P = Work done by the body / time taken.

(i) The S.I. unit of power is watt (W).

(j) 1 H.P. = 746 W.