Advertisements
Advertisements
Question
A body of mass m falls down through a height h. Obtain an expression for the work done by the force of gravity.
Advertisements
Solution
Assume that a body A with mass'm' is elevated 'h' above the ground, and B falls.
Force acting on 'm' at A is mg force of gravity.
Displacement = height = h
Work done in falling W = force × displacement
W = mg × h
The formula for the amount of work that gravity has done is W = mgh.
APPEARS IN
RELATED QUESTIONS
Write true or false of the following statement.
The energy of flowing water can be converted into electric energy (electricity).
Define the term kinetic energy. Give one example of a body which possesses kinetic energy.
Name the type of energy (kinetic or potential) possessed by the following:
A moving cricket ball.
Name the form of mechanical energy, which is put to use.
MULTIPLE CHOICE TYPE:
The ultimate source of energy is:
(a) wood
(b) wind
(c) water
(d) sun
Name the energy changes for the following:
pendulum
What kind of energy is possessed in a situation when?
A horse running along a level road
What is the main energy transformation that occur in:
Photosynthesis in green leaves.
Give one example when:
Kinetic energy to potential energy.
Calculate the kinetic energy of a body of mass 0.1 kg. and momentum 40kg m/s.
