Newton’s Laws
Which law is also called the law of inertia?
Newton’s First Law
What happens to gravity if mass increases?
It increases.
Speed = ?
Distance ÷ Time
What is friction?
Force opposing motion between surfaces.
Momentum = ?
Mass × Velocity
Which law is F = ma?
Newton’s Second Law
What happens to gravity if distance doubles?
It decreases (1/4 strength).
Velocity includes what that speed does not?
Direction
What is air resistance?
A type of friction in air.
What is the law of conservation of momentum?
Total momentum is conserved in a closed system.
Which law explains rockets launching?
Newton’s Third Law
What keeps planets in orbit?
Gravity + inertia.
What does the slope of a distance-time graph represent?
Speed/velocity
If net force = 0, what happens to motion?
Object stays at rest or constant velocity.
Two skaters push off. What happens to momentum?
Each moves with equal and opposite momentum.
A ball rolling stops because of friction. Which law?
Newton’s First Law
What is weight a measure of?
The force of gravity on mass.
Acceleration means a change in…?
Velocity (speed or direction).
What is centripetal force?
Force pulling toward center of circular path.
What happens to momentum in a collision if no external force acts?
It is conserved.
Explain how Newton’s 3rd law applies when you jump off a small boat.
You push the boat backward as you move forward.
Why do astronauts in space feel weightless?
They are in free fall around Earth.
If a car goes from 0 to 20 m/s in 5 seconds, what is its acceleration?
4 m/s²
Give an example of centripetal force in real life.
Car turning, roller coaster loop, orbit.
A 2 kg ball at 3 m/s hits a 1 kg ball at rest. What is total momentum?
6 kg·m/s