This law states that an object maintains its motion unless an unbalanced net force acts on it.
What is Newton's First Law?
According to this law, acceleration depends on net force and mass.
What is Newton's Second Law?
Third law force pairs are equal in size and ______ in direction
Every action has an equal and _______ reaction
Opposite (Equal and opposite)
These 2 factors determine an object's kinetic energy.
Speed and Mass
A box slides right across the floor. State the direction of friction.
What is left?
A ball travels across a perfectly frictionless surface after the push ends. Describe its motion.
Continuing at the same speed and same direction
The same net force acts on a 2kg cart and a 6kg cart. Which cart accelerates more?
2kg Cart
50N on the student (opposite direction)
A cart's mass doubles while its speed remains constant. Describe the change in kinetic energy.
A flat sheet of paper falls more slowly than a crumpled sheet because it experiences more of this force.
What is Air Resistance?
A book experiences 12N upward and 12N downward. Describe the forces (balanced v unbalanced) and its motion.
Two identical carts are experiencing net forces of 10N and 5N. Identify which accelerates more.
Cart experiencing 10N of force
A car collides with a bike. Compare the force of the car on the bike with the force of the bike on the car
Equal forces in Opposite directions
A cart’s speed doubles while its mass remains constant. Describe the change in kinetic energy.
Kinetic energy became 4x as large
A sliding object loses kinetic energy because friction transfers energy to these parts of the system.
What are the surfaces (floor) and surroundings?
When a bus suddenly stops, passengers continue moving forward because of this property.
(Look at your vocab wall)
What is Inertia?
A 12N net force acts on a 3 kg cart
Calculate its acceleration (find a)
Fnet = m * a
A car and bike experience equal collision forces, but the bike accelerates more. Why?
Two identical carts hit a wall. Cart A’s force graph peaks at 800 N, while Cart B’s peaks at 300 N. Identify which collision has the larger peak force.
Cart A's collision
Students change cushioning thickness and measure peak force. Identify the independent and dependent variables.
Cushioning Thickness (Independent Variable)
Peak Force (Dependent Variable)
Rex was pushed with 30N of force to the right and had 12N of friction back on him pushing left. Give the net force and predict its motion
What is 18N to the right, causing Rex to accelerate right
Cart A experiences 12 N on 3kg. Cart B experiences 10N on 2kg. Identify which cart accelerates more and by how much more?
Ex: Cart B by 2 more m/s^2
Cart B by 1 m/s^2 (5 vs 4)
During the wrestling demo, one student moved backward while the other remained standing. Evaluate the claim that the starting student exerted a larger interaction force.
Two identical carts hit identical barriers at the same speed. Cart A carries an additional mass, while Cart B does not. Predict which cart will likely produce the greater peak force and explain why.
Cart A because its greater mass gives it more kinetic energy at the same speed, which can produce greater peak force during the collision
A group tests thin and thick foam once each and concludes that thick foam always works better. Evaluate their conclusion.
What is the conclusion is not sufficiently supported because they need repeated trials, controlled conditions, averages, and possibly additional thicknesses?