ICSE-VIII-Physics

04: Energy Class 8 Physics

with Solutions -
  • #2
    Fill in the blanks (a) Work is said to be done by a forte only when ____ (b) Work done = Force × ____ (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 body is due to its _____ (f) Gravitational potential energy U = mass × force of gravity on unit mass × ____ (g) Kinetic energy = 1/2 × mass × ____ (h) Power P = _____/time taken. (i) The S.I. unit of power is ____ (j) I H.P. = ____
    Ans : (a) Work is said to be done by a forte only when the body moves. (b) Work done = Force × distance moved in 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 body is due to its state of motion. (f) Gravitational potential energy U = mass × force of gravity on unit mass × height. (g) Kinetic energy = 1/2 × mass × (speed)2 (h) Power P = work done/time taken. (i) The S.I. unit of power is watt (j) I H.P. = 746 W
  • #2-a
    Work is said to be done by a forte only when ____
    Ans : Work is said to be done by a forte only when the body moves.
  • #2-b
    Work done = Force × ____
    Ans : Work done = Force × distance moved in direction of force.
  • #2-c
    The energy of a body is its capacity to do ____
    Ans : The energy of a body is its capacity to do work.
  • #2-d
    The S.I. unit of energy is ____
    Ans : The S.I. unit of energy is joule.
  • #2-e
    The potential energy of a body is due to its _____ and kinetic energy of body is due to its _____
    Ans : The potential energy of a body is due to its state of rest or position and kinetic energy of body is due to its state of motion.
  • #2-f
    Gravitational potential energy U = mass × force of gravity on unit mass × ____
    Ans : Gravitational potential energy U = mass × force of gravity on unit mass × height.
  • #2-g
    Kinetic energy = 1/2 × mass × ____
    Ans : Kinetic energy = 1/2 × mass × (speed)2
  • #2-h
    Power P = _____/time taken.
    Ans : Power P = work done/time taken.
  • #2-i
    The S.I. unit of power is ____
    Ans : The S.I. unit of power is watt
  • #2-j
    I H.P. = ____
    Ans : I H.P. = 746 W