1st Law
2nd Law
3rd Law
Motion Math
100
What is another name for Newton’s 1st Law?
The law of _______________
inertia
100
What is Newton's second law in formula form?
F = ma
a = F/m
100
What is Newton’s third law?
For every action, there is an equal and opposite reaction.
100
What variable has units of "m/s²"?
Acceleration
200
According to Newton’s 1st Law, what happens to an object at rest if the forces on it are balanced?
It stays at rest
200
If you double the force on an object, what happens to its acceleration?
It doubles
200
When you jump off a skateboard, why does the skateboard move backward?
You push the skateboard backwards and the skateboard pushes you forward.
200
A 50 N force moves two objects: one 5 kg and one 10 kg. Which accelerates faster?
The 5 kg object
300
You’re riding in a car and it suddenly stops — why does your body move forward?
Your body is in motion moving forward, and when the car stops, your body continues moving forward because of its inertia.
300
If you double the mass but keep the same force, what happens to acceleration?
It is cut in half
300
What two forces are involved when a rocket launches from the ground into the air?
The rocket pushes gases down, gases push the rocket up
300
If a 10 N force moves a 5 kg object, what’s the acceleration?
a = F / m
a = 10 / 5
a = 2 m/s^2
400
What will cause an object to change its motion?
an unbalanced force
400
A 2 kg object accelerates at 3 m/s². What is the force?
6 Newtons
400
Use Newton's third law to describe how using a paddle helps a boat move.
When the paddle pushes the water backward, the water pushes the paddle (and the boat) forward.
400
What is the acceleration of an object if it speeds up from 3 m/s to 6 m/s in 2 s?
a = (Δv)/(Δt)
a = (6-3)/2
a = 1.5 m/s^2
500
If you kick a soccer ball on grass, why does it stop instead of rolling forever?
Friction is an unbalanced force that slows it down
500
Why do heavier objects need more force to move?
They have more mass (inertia), so they resist motion more
500
Explain how walking uses Newton’s 3rd Law.
Your foot pushes backward on the ground; the ground pushes you forward
500
A 3 kg cart accelerates at from 2 m/s to 10 m/s in 4 s. What is the net force on the cart during this time period?
a = (Δv)/(Δt)
a = (10-2)/4 = 2 m/s^2
F = ma
F = (3)(2) = 6N