Speed, velocity, acceleration
Write the formula for speed.
speed = distance / time
What happens to an object's motion if forces are balanced?
State Newton's first law
Objects resist changes in motion unless acted on by an unbalanced force
F=ma
You’re riding in a car and suddenly stop. You keep moving forward. Which law is this?
Newton's first law
Write the formula for acceleration.
acceleration = (final velocity - initial velocity) / time
What happens to an object's motion if forces are unbalanced?
The motion changes (speeds up, slows down, or changes directions)
State Newton's 2nd law
F=ma
A 5 kg object accelerates at 2 m/s². What is the force?
10 N
A baseball bat hits a ball. The bat pushes the ball forward; the ball pushes back. Which law?
Calculate the speed (if needed) and add the direction.
Two students are pushing a desk. One pushes the desk to the right with 40 N, and the other pushes to the left with 25 N. Are the forces balanced or unbalanced?
Unbalanced
State Newton's 3rd law
Every action has an equal and opposite reaction
A cyclist travels 600 m in 120 seconds. What is their speed?
5 m/s
A bowling ball is harder to push than a tennis ball. Which law explains this?
2nd law
A runner running west travels 300 meters in 60 seconds. What is her velocity?
5 m/s west
A box has is being pulled to the left with 150 N of force and to the right with 150 N of force. Are the forces balanced or unbalanced, and what what will happen to the motion of the box?
Balanced, it will not change its motion
A 20 kg box is pushed with a force of 80 N. What is its acceleration?
4 m/s/s (or 4m/s2)
A box is pushed across the floor. If friction and the force you apply to push it are equal, what happens to the box?
It moves at a constant speed (balanced forces)
A skateboarder speeds up from 2 m/s to 14 m/s in 6 seconds. What is his acceleration?
2 m/s/s (or 2m/s2)
A student is pulling a wagon forward with a force of 120 N. Friction pulls backward with a force of 90 N. The wagon has a mass of 60 kg. What will happen to the wagon’s motion?
The wagon will accelerate forward
A rocket launches by pushing gases down while it blasts up. Which law explains this?
3rd law
A runner runs for 200 seconds at a speed of 10m/s. What distance do they travel?
2000 meters
A rocket experiences a force of 9,600 N and accelerates at 12 m/s². What is the mass of the rocket?
800 kg