Force, Motion & Energy
SOL 4.2
The student will investigate and understand
characteristics and interaction of moving objects.
Key concepts include
motion is described by an object’s direction and
speed;
forces cause changes in motion;
 friction is a force that opposes motion; and
moving objects have kinetic energy.
Objects’ Positions
(Relative Location)
 “The
position of an object can be
described by locating it relative to
another object or to the background.”
 Example: The Oil is in front of the
windmills. The Worker
is beside the oil.
Showing Movement
“Tracing and measuring an object’s position
over time can describe its motion.”
 Use Graphs to
60
show your data.
50
 Example: I dropped
40
a ball three times
30
and measured the
20
height of each bounce.

10
0
1st
2nd
3rd
4th
Bounce Bounce Bounce Bounce
Try 1
Try 2
Try 3
SPEED
 “Speed
describes how fast an object is
moving.”
 Example: The Police Officer Clocked
the Driver going 68 MPH down the
highway.
Types of Energy
“Energy may exist in two states: kinetic or
potential.
 Kinetic Energy is the energy of motion.”
 Potential Energy is stored energy.

Kinetic energy is energy of motion.
Potential energy is converted into kinetic
energy. Before the yo-yo begins its fall it
has stored energy due to its position. At the
top it has its maximum potential energy. As it
starts to fall the potential energy begins to
be changed into kinetic energy. At the
bottom its potential energy has been
converted into kinetic energy so that it now
has its maximum kinetic energy.
FORCE
 “A
force is any push or pull that causes
an object to move, stop, or change
speed or direction.”
 Example: this wagon can be pulled,
pushed, stopped, and have it’s direction
changed by a person.
Force – Easy or Difficult
“The greater the force, the greater the change in
motion will be.
Heavy
 The more massive an object, the less effect a
Load –
given force will have on the object.”
Lots of
 Meaning – Lighter objects take less energy to
move/change. Heavier objects take more energy. Energy –
YES
 The Greater the Force used the quicker or easier
Moving
the object will move. The Lesser the Force used
the slower or harder the object will move.
Heavy
Load –
Light Load No
Heavy Load Easy
Energy –
Harder
NO
Moving

ROUGH
SMOOTH
Friction
“Friction is the resistance to motion created by two
objects moving against each other. Friction creates
heat.”
 Friction is what will make moving something harder:
texture of surface, elevation of surface, weight of object.
 Friction tries to STOP or SLOW an object.
 The Smoother or Flat the LESS Friction. The Steeper
and Rough the MORE Friction.
FLAT
HILLY

Moving?
 “Unless
acted on by a force, objects in
motion tend to stay in motion and
objects at rest remain at rest.”
 If no person, animal or natural event
happens things will stay the same;
either moving or still.