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The website has the complete lesson note for all the subjects in secondary school but this piece showcases the JSS2 Basic Science Lesson Note on Work; Energy and Power. You can use the website search button to filter out the subject of interest to you.

TOPIC: WORK, ENERGY, AND POWER 1

CONTENT:  1. Meaning of work, energy and power.

1. Meaning of potential and kinetic energy.

MEANING OF WORK

Work is said to be done whenever a force or load moves through a distance. i.e., work=force x distance moved in the direction of the force (fxd).

Mathematically

W(d)=fxd

The unit of work is joules with symbol J.

Force

Force is that which changes a body’s state of rest or uniform motion in a straight line. It can as well be expressed as:

Force=mass x acceleration

i.e.   F=m x a

Where:   F=force, M=mass and A=acceleration

The unit of force is Newton(N).

If force = mass x acceleration

Work can be given as: Work = Mass x acceleration x distance.

Also, W=FxS

Where,

W= Work done is measured in Joules (J)

F= Force applied in Newton (N)

S= Distance covered by the body in metres (m)

This is a simple formula that can be used to calculate work done especially against gravity.

ENERGY

Energy is the capacity for doing work or the ability to do work.  Energy has the same unit as work, that is, energy is measured in joules.

POWER

Power is defined as the rate at which work is done or the rate of transfer of energy or the rate of doing work. i.e.  work done divided by time