PhysicsSSS1 FirstTerm
WEEK11
Work, EnergyandPower
PerformanceObjectives
Students should be able to:
1. Determine work, energy and power
2. Explain work done in a force field
Content
Determination of Work, Energy and Power
In physics, a force is said to do work when it acts on a body so that there is a displacement of the point of application, however small, in the direction of the force. Thus, a force does work when it results in movement. The work done by a constant force of magnitude F on a point that moves a distance d in the direction of the force is the product,
W=Fd
The SI unit of work is the joule (j)
W=F(cosƟ) ∆x where cosƟ is the component of force in the direction of motion.
If workƟ=0
Then
W=F∆x

Energy  
In Mechanics, Energy of a body is a measure of its ability to do work. Energy, like mass, is a scalar physical quantity.
Energy exist in many forms e.g. thermal energy,.... View More