Force, Motion & Energy SOL 4.2

The student will investigate and understand characteristics and interaction of moving objects. Key concepts includemotion is described by an object’s direction and speed;forces cause changes in motion; friction is a force that opposes motion; andmoving 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

show your data. Example: I dropped

a ball three times and measured the height of each bounce.

0

10

20

30

40

50

60

1stBounce

2ndBounce

3rdBounce

4thBounce

Try 1Try 2Try 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. The more massive an object, the less effect a

given force will have on the object.” Meaning – Lighter objects take less energy to

move/change. Heavier objects take more energy. The Greater the Force used the quicker or easier

the object will move. The Lesser the Force used the slower or harder the object will move.

Light Load - Easy

Heavy Load - Harder

Heavy Load –

No Energy –

NO Moving

Heavy Load – Lots of

Energy – YES

Moving

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.

FLATHILLY

SMOOTH ROUGH

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.