Transcript WORK AND ENERGY

WORK AND ENERGY
Work
Work is said to be done whenever the
application of the force produces a
change.
A change can be the change in
velocity
position
shape
temperature
ENERGY
The ability to do work is called energy.
Different Kinds of Energy
Kinetic Energy
Potential Energy
Kinetic Energy
The ability to do work based on
motion is called kinetic energy
Potential Energy
The energy possessed by objects
because of their position or shape.
Identify Kinetic and Potential
Energy
An object can have
both potential and
kinetic energy.
An aeroplane flying at a height has
both potential and kinetic energy
The sum of the
potential
and
kinetic energies of
an object is called
mechanical
energy.
Energy can neither be created nor
destroyed.
It can only be converted from one
form to another or transferred from
one object to another.
Rubbing Palms produces
heat energy.
Work- Formula
How much work is done – depends
on the force applied to produce the
motion.
The amount of work done
Depends on
The force applied to do the work.
The distance travelled
Therefore work done= force X distance
Unit of Work
Unit of Force- Newton
Unit of Distance- Meter
Therefore, the unit of Work= Newtonmeter
Newton-meter is also called Joule in
the name of British scientist James
Joule.
Work done in lifting mass to a
height
Earth attracts the mass m
with a force = mg
g is the acceleration due
to gravity.
h is the distance through
which the object has
moved.
Work done…
Therefore the work done in raising the
books of mass m to height h is mgh.