Force and Motion
Why is it difficult to walk quickly on a frozen sidewalk?
There is very little friction.
Is work done if you push a heavy box but it does not move?
No
Which simple machine helps move objects to a higher place using a slope?
Inclined plane
What force pushes upward on a chair when you sit on it?
Normal force
What is the term for an object continuing its motion unless acted on by another force?
Inertia
What must you know besides net force to calculate acceleration?
The object’s mass
A student carries books across the room. What two things are needed for work to happen?
Force and movement
What class lever is commonly seen in a wheelbarrow?
Second-class lever
What force occurs between magnets without touching?
Magnetic force
What type of force happens when two surfaces rub together?
Friction
What force keeps the Moon moving around Earth?
Gravity
Two students lift identical bags, but one finishes faster. Who has greater power?
The student who finishes faster
Which simple machine is used to split or cut objects?
Wedge
What type of force acts between charged objects?
Electrical force
Name one machine that uses a wheel and axle.
Bicycle / Doorknob / Pencil sharpener/ ETC...
If two teams pull equally hard in tug-of-war, what happens?
The rope does not move.
What unit is used to measure work?
Joules
What simple machine is found on jar lids and bolts?
Screw
What force helps keep planets in orbit around the Sun?
Gravity
Which simple machine changes the direction of a force using a rope and wheel?
Pulley
On a speed-time graph, what does a flat horizontal line mean?
The object is moving at a constant speed.
A machine helps make work easier by changing what?
Force
Why do people use machines?
To make work easier
What force holds the tiny particles inside the nucleus together?
Nuclear force
Name one way a machine can change force and give an example.
Example: A pulley changes the direction of force.