Download U4 Kinetic-Potential Energy

Warm-up:
What types of energy
do you think are
shown in the video?
1) … 2) … 3)
Cooking with Snoop
Intro to
Energy
Chapter 9
What is Energy?
Energy:
the ability to do work.
Work: done when a force causes
an object to move in the
direction of the force.
Work  a transfer of energy.
Work
& Energy are measured in
joules (J).
What is Energy?
KINETIC
CHEMICAL
ELASTICPOTENTIAL
Two Types of Energy
Potential
Energy is the energy
of position.
Kinetic Energy is the energy of
motion.
Kinetic Energy
 Kinetic
energy is the energy of an
object due to its motion.
 All moving objects have kinetic
energy.
 We can determine how much
kinetic energy an object has with
this formula:
KE = mv2
2
m = mass in kilograms (kg)
v = velocity (speed) in meters per
second (m/s) (not Volume!)
Practice
A car weighing 1,200 kg is moving
at a speed of 20 m/s, what is its
kinetic energy?
KE = 1,200 (20)2
2
KE = 1,200 (400)
2
KE = 480,000
2
KE = 240,000 J
Potential Energy
Potential
energy is the energy
of an object due to its position,
shape, or condition.
Potential energy is also
considered to be an object’s
stored energy.
Two types of potential energy:
Gravitational
Potential Energy
Elastic Potential Energy
Gravitational
Potential Energy
Gravitational
Potential Energy is
the energy stored in an object
due to the Force of Gravity.
We can determine how much
gravitational potential energy
an object has with this formula:
GPE = w x h
w = weight in newtons (N)
h = height in meters (m)
Practice
A ball weighing 13 N is held at a
height of 1.5 m, what is its
gravitational potential energy?
GPE = 13 x 1.5
GPE = 19.5 J
Elastic
Potential Energy
Elastic
Potential Energy is the
energy stored in an object from
being stretched or wound-up.