Define force
A push or pull interaction between two objects
State the unit of measurement for force
Newton (N)
When will gravity be the strongest?
A. The further away you are from an object
B. The closer you are to an objecT
C. The faster your relative speed is to an object
Which has more air resistance - a feather, or a stone?
A feather
Name an example of surface tension in action.
Water striders, meniscus, why it hurts when you belly flop
Define gravity
A non-contact force that attracts objects to each other
List the 5 actions a force can make an object do
Accelerate
Decelerate
Stop
Change shape
Change direction
State a force that acts against gravity
Normal force
Air resistance
Explain how air resistance is increased on an object
By changing it's shape and size
The following forces are balanced
TRUE
Define mass
The amount of matter or 'stuff' in an object
Which would be an example of an unbalanced force?
A. A plate sitting on a dining table
B. A ball at the top of a hill that is not moving
C. Earth orbiting the Sun
D. A baseball that has been thrown to home plate.
If you were to go to the moon, how would you feel?
A. Weightless
B. Heavy
C. Huge
D. Tiny
In what direction does air resistance act on an object that is falling straight down?
A. Down
B. Right
C. Left
D. UP
Calculate the amount of gravitational force a dog that has a mass of 30kg will experience on Earth.
FALSE
Define weight
The force of gravity on an object
Why does a book on a table not move?
The force of gravity is pushing down, the normal force of the table is pushing up. The forces are balanced.
Is there more gravitational force between you and the Earth or an elephant and the Earth? and Why?
Elephant - more mass
MINDMELD
Electrostatic Force
Name three types of non-contact forces.
Electrostatic, Magnetic, Gravity
Define air resistance
The force that air exerts on objects moving through it
What is the net force?
4000 N left
Explain why planets in our solar system do not 'escape into space'
The planet's are pulled towards the Sun by a gravitational force. The force is not strong enough to pull the planets into the sun. But, it is strong enough to keep them from escaping into deep space.
Explain why air resistance increase as speed increases
The faster something is falling, the more 'air' the object encounters, the more resistance there is on it.
Terminal velocity is when a falling object is accelerating while it is falling.
FALSE