Newton's First Law
What is the the tendency of an object to resist a change in its motion?
Inertia
What is the equation for Newton’s Second Law?
F = m × a
State Newton’s Third Law.
For every action, there is an equal and opposite reaction.
What is the acceleration due to gravity on Earth?
9.8 m/s² (accept 10 m/s² for simplicity).
A 2 kg box is pushed with a force of 10 N. What is its acceleration?
5 m/s².
If a soccer ball is at rest on the field, what must happen for it to start moving?
A force must act on it (like a kick).
If two objects have the same mass, which one accelerates more: the one with a bigger force or smaller force?
The one with the bigger force.
When you push against a wall, what does the wall do?
It pushes back with the same force.
In free fall (no air resistance), which falls faster: a heavy rock or a light rock?
They fall at the same rate.
A force of 12 N accelerates a 3 kg object. What is the acceleration?
4 m/s².
Why do passengers lunge forward when a car suddenly stops?
Their bodies keep moving due to inertia.
A force of 10 N is applied to a small cart, and it accelerates. If the force is doubled, what happens to the acceleration?
It doubles.
Why does a balloon fly around the room when you let go of it?
Air rushes out one way, pushing the balloon the opposite way.
After 1 second of free fall, how fast is an object moving?
About 10 m/s downward.
A 4 kg object accelerates at 2 m/s². What is the force?
8 N
If there were no friction or air resistance, what would happen to a moving hockey puck on ice?
It would keep moving at the same speed forever.
What happens to acceleration if the mass of an object increases but the force stays the same?
The acceleration decreases.
A rocket launches into space. What are the action and reaction forces?
Action: Rocket pushes gases down. Reaction: Gases push rocket up.
After 3 seconds of free fall, how fast is an object moving?
About 30 m/s downward.
A force of 15 N is applied to move a 5 kg block. What is the acceleration?
3 m/s².
Give one real-life example of Newton’s First Law in safety equipment.
Seatbelts, airbags, helmets, etc.
Explain why pushing a full grocery cart is harder than pushing an empty one.
The full cart has more mass, so it needs more force to accelerate.
When a swimmer pushes backward on the water, why do they move forward?
The water pushes them forward with equal and opposite force.
Why does a feather fall slower than a rock on Earth, but the same in a vacuum?
Air resistance slows the feather on Earth; in a vacuum, there’s no air resistance.
A 10 kg box is pushed and accelerates at 2 m/s². What is the force?
20 N.