UI
Toolbox
  • Dictionary
    Dictionary
  • Calculator
    Calculator
Grade - 8 (BLE) Physics Work

A boy standing for the whole day feels tired. Has he done any work? Why does he feel tired?

A boy standing for the whole day feels tired. Has he done any work? Why does he feel tired?

Share My Answer
1

1 Answer

A boy standing for the whole day has not done any work because he hasn't changed his position but he feels tired because he is applying force against the force of gravity.

To do the work he should have made some displacement in the direction of the force. Had he moved horizontally on the surface he would have done work against the friction but not work against gravity. Because to do work against gravity an object should move in the direction of gravitational force (vertically)

1

Comments

Things to Remember From Work

  1. Work is said to be done if any object changes its position by the application of force on it.
  2. The SI unit of work is the joule
  3. Generally, there are two types of work
    1. work against gravity,
    2. work against friction.
  4. The work done by an object is zero if
    1. Displacement is zero, and
    2. Force is perpendicular to the displacement.

Topics from Physics

Physical Quantities 27 Electricity & Magnetism 48 Motion 8 Measurement 4 Electricity 166 Physical Optics 80 Waves 117 Force 51 Heat 137 Laws of Motion 1 Light 100 Pressure 139 Thermodynamics 1

Related Questions