Newton's First Law
A soccer ball rolls across the grass and eventually stops. What force causes it to slow down?
Friction
Two students push identical shopping carts. Student A pushes with twice as much net force. How does their cart's acceleration compare?
Student A's cart accelerates twice as much.
When a swimmer pushes water backward, what pushes the swimmer forward?
The water
A 15 kg box accelerates at 4 m/s². What net force acts on it?
60 N
A soccer player kicks a stationary ball, causing it to move. Which law explains why the ball was initially at rest?
Newton's 1st Law
A passenger is thrown forward when a car suddenly stops. Why does their body keep moving?
Inertia
A 10 kg object and a 20 kg object experience the same net force. Which accelerates faster, and why?
The 10 kg object because it has less mass.
A rocket launches upward by pushing gases downward. Are the forces equal or is the upward force greater?
The forces are equal in magnitude and opposite in direction.
A 50 kg object experiences a net force of 200 N. What is its acceleration?
4 m/s²
A player kicks a soccer ball and a bowling ball with the same net force. The soccer ball accelerates faster. Which law explains this?
Newton's 2nd Law
Two objects are sitting still: a basketball and a bowling ball. Which has more inertia, and why?
The bowling ball because it has more mass.
A student pushes a box with 50 N of force, while friction pushes against it with 20 N. What is the net force?
30 N forward
A student pushes against a wall with 100 N of force. How much force does the wall push back with?
100 N
A soccer ball accelerates at 20 m/s² when kicked with a net force of 10 N. What is its mass?
0.5 kg
A basketball player jumps by pushing down on the floor. The floor pushes them upward. Which law explains this?
Newton's 3rd Law
A hockey puck slides across ice longer than a soccer ball rolls across grass. Why?
The ice creates less friction.
A 5 kg object accelerates at 4 m/s². If its mass doubles but the net force stays the same, what is its new acceleration?
2 m/s²
When a person jumps off a small boat, the boat moves backward. Why?
The person pushes the boat backward, and the boat pushes the person forward.
A 20 kg sled is pulled forward with 100 N of force. Friction pushes backward with 40 N. What is the sled's acceleration?
3 m/s²
A student standing on a moving bus falls backward when the bus suddenly accelerates forward. Which law explains this, and why?
Newton's 1st Law. Inertia causes their body to resist the change in motion.
An astronaut pushes a tool away in space. If no outside forces act on it, what will happen to the tool?
It will continue moving at a constant speed in a straight line.
A car's mass stays the same, but the net force acting on it triples. What happens to its acceleration?
Its acceleration triples.
A truck crashes into a small car. Which vehicle experiences the greater force during the collision?
Neither. Both experience equal and opposite forces.
A 1,500 kg car experiences a forward engine force of 6,000 N and 1,500 N of resistance. What is its acceleration?
3 m/s²
Two students wearing roller skates push against each other. One student has a mass of 50 kg, and the other has a mass of 100 kg. Who accelerates faster, and which two laws explain the situation?
The 50 kg student. Newton's 3rd Law explains the equal forces, and Newton's 2nd Law explains the greater acceleration.