Work and Energy
By Julian Gonzalez
Work Done by a constant force
• Work is defined as the product of the
magnitude of the displacement times the
component of the force parallel to the
displacement.
W=F||d
Work is measured in newton-meters.
1N·m=1J
Kinetic energy, and the workenergy principle
• An object in motion has the ability to do
work and thus can be said to have energy.
The energy of motion is called kinetic
energy.
Wnet =KE² - KE¹
The net work done on an object is equal to
the change in its kinetic energy this is
known as work-energy principle.
Potential Energy
• Potential energy is the energy associated
with forces that depend on the position of
a body and the surroundings.
PE of gravity
WG =-mg(y²-y¹)
Power
• Power is defined as the rate at which work
is done.
P=Energy transformed / time
Power is measured in joules per sec.
1W = 1J/s
horsepower is defined as 550ft·lb/s= 746W