Newton's Laws
What is inertia?
An object’s resistance to a change in motion.
What equation connects force, mass, and acceleration?
F = ma
During a collision, the two objects exert forces that are equal and
Opposite
What type of energy does a moving object have?
Kinetic Energy
What are criteria?
Requirements a successful design should meet.
A passenger moves forward when a car suddenly stops. Which law explains this?
Newton’s First Law
A 6 kg cart accelerates at 4 m/s². Find the force.
24 N
One object pushes another with 40 N during a collision. How much force does the second object exert back?
40 N in the opposite direction
Name TWO forms of energy kinetic energy can transform into during a collision.
Sound and thermal energy
What are constraints?
Limits on a design, such as time, materials, cost, or size.
A swimmer pushes backward on a wall and the wall pushes the swimmer forward. Which law?
Newton's Third Law
A 24 N force acts on a 6 kg object. Find acceleration.
4 m/s²
A light marble and heavy steel ball collide. Which has the greater acceleration?
The light marble
A tennis ball squishes when it hits the ground. What energy can temporarily be stored while it is deformed?
Elasic Potential energy
Why can cushioning help protect a phone during a collision
It deforms/absorbs impact and reduces the damaging effects of the collision.
Two carts receive the same force. One is empty and one is full of books. Which accelerates more, and which law explains it?
Empty cart; Newton’s Second Law
20 N acts right and 13 N acts left. Find the net force.
7 N right
A truck and small car collide. Which one exerts the greater collision force?
Neither; they exert equal and opposite forces.
Why does a Newton’s cradle eventually stop?
Energy leaves the system as sound/thermal energy and forces such as friction act.
Name one criterion AND one constraint for a protective phone case.
Answers vary; e.g. criterion: prevents screen damage; constraint: limited cost/materials.
Name all three laws in this situation: a soccer ball travels toward a wall, hits it, and bounces backward.
1st—inertia until force acts; 2nd—force causes acceleration/change in velocity; 3rd—ball and wall exert equal/opposite forces.
A 50 N force acts right and 20 N acts left on a 10 kg object. Find net force AND acceleration
30 N right; 3 m/s² right
Two objects collide. Object A has much less mass than Object B. Compare their forces AND accelerations.
Equal/opposite forces; A has greater acceleration.
A moving ball hits another ball and you hear a sound. What happened to the energy?
Kinetic energy was transferred between objects and some transformed into sound/thermal energy.
Explain how Newton’s Laws can help engineers protect a smartphone screen during a collision.
Use cushioning/deformation to reduce damaging effects while accounting for collision forces and acceleration