Vocabulary 1
Force of pushing or pulling between magnetic poles
Magnetism
Push or pull that causes an object to move, stop, or change direction
Force
What force causes a ball to fall back down?
Gravity
What always acts in pairs?
Forces
If Miss Gerecke and Mrs. Harter are on opposite sides of the cabinets pushing them and they don't move, the forces are what?
Balanced
Amount of work done for each unit of time
Power
Change in object's motion, such as speeding up, slowing down, or changing direction
Acceleration
What force makes your hands heat up when you rub them together?
Friction
If a magnet can't hold a paper to a door frame, the forces acting on the magnet are what?
Unbalanced
The metric unit of power is a what?
Watt
Use of force to move an object through a distance
Work
Force that opposes motion when two surfaces rub against each other
Friction
What do magnets have that acts on objects without touching them?
A force
In finding the net force, what do you have to do if the forces are acting on the object in the same direction? (it's an operation)
Add
In finding the net force, if the forces are acting on an object in opposite directions, what operation do you have to do to calculate the net force?
Subtract
Value of combined forces on an object
Net Force
Machine
What two simple machines is a shovel made up of?
A lever and wedge
What can change the size or direction of a force?
A machine
What causes the needle of a compass to point north and south?
Earth's magnetic field
Opposing forces of which one force is greater than the other
Unbalanced Forces
Forces equal in size and opposite in direction
Balanced Forces
Two people try to push a 4,000 Newton crate, but it doesn't move, how many Joules of work have they done?
Zero Joules
If you lift a 3-newton book 1 meter off your desk, how many joules of work do you do?
3 joules of work
What is the net force when a force of 100 newtons pushes against a force of friction of 80 newtons?
20 newtons