Transcript Energy and Work

Energy and Work
Energy- the ability to cause a
change.
Ex: Baseball hitting a window.
The baseball has energy
because it caused the change.
 Different forms of energyradiant, electrical, chemical,
thermal and nuclear.
Kinetic energy (KE)- the
energy in the form of motion.
Ex: anything moving
- The amount of kinetic energy on
an object depends on
(1.)mass (more mass = more KE)
(2.)velocity (more velocity = more
KE)
Potential energy (PE)- stored
energy.
- The amount of potential energy
depends on its position. The
greater position = more PE.
Ex: Flowerpot on windowsill.
The higher the windowsill, the
greater PE so greater KE.
Mechanical energy- the total
amount of kinetic and potential
energy in a system.
Ex: Roller coasters. At the top of
hills, they have high PE and low
KE. When they go downhill,
then they have low PE and high
KE.
Law of conservation of
energy- Energy can’t be
created nor destroyed (under
ordinary conditions)…..energy
just changes forms.
Ex: KE is not created…it is
changed from PE.
Work- a transfer of energy
through motion.
-When force acts over a distance
in the direction of an object’s
motion, work is done.
2 things to see if work is done.
1.Movement
2.Motion in same direction as the
force.
Work equation
Variable
W = Work
F = Force
d = distance
Ending Units
Joules (J)
Newtons (N)
meter (m)
Work Equation
W=Fxd
F=W/d
d=W/F
W
F
.
.
.
.
X d