Vocabulary
The type of force that causes an object to change its motion.
An unbalanced force
Finish the phrase: "An object in motion stays in motion and...
"an object at rest stays at rest unless acted on by an unbalanced force"?
the formula for Newton's 2nd Law
F = ma
Newton's 3rd Law states that...
every action has an equal and opposite reaction.
A tennis ball is served, the tennis player on the other side of the net swings at the ball but misses. This law explains why the ball stays in motion until it hits the fence.
Newton's 1st Law
What is the force that pulls two objects toward one another, generally downward?
gravity
In the following example, what is the unbalanced force: A car is driving down the street, but comes to an abrupt stop when it hits a tree.
the tree
Finish Newton's 2nd Law: Acceleration occurs when...
a force acts on a mass.
Explain how walking demonstrates Newton's 3rd Law
Your foot pushes with a force down and backwards on the ground, and the ground pushes with a force up and forward on your foot, propelling you forward.
Which of Newton's Laws take force into consideration?
What is "all of them"?
The distance from one object to another is changing
motion
Why do we wear a seat belt?
The car's brakes are designed to stop the car's forward motion, not yours. If the car stops suddenly, you will continue moving forward until your forward motion is stopped by the steering wheel, windshield, or the ground. The seat belt applies a force opposite of your motion and stops you.
If a force of 10N occurs on a mass of 2kg, what must be the acceleration? (remember to use appropriate units!)
5 m/s
A swimmer pushes off the side of the pool and is propelled forward by the force of the pool exerting a force on the swimmer's foot. Explain this in terms of Newton's 3rd Law.
the action is pushing off of the side of the pool, the reaction is being propelled forward
Mrs. Albicker is going down the sidewalk on her skateboard; Mr. Kirby decides to get on too. What will Mr. Albicker have to do to keep the skateboard moving at the same velocity?
push with more force
A change in a moving object's speed or direction
acceleration
Another name for Newton's First Law.
Law of Inertia
Calculate the force of a .025 kg ball accelerating at 45 m/s^2.
1.125 N
If you push on a wall with 30 N of force, the wall will push back with how much force?
30 N
Mrs. Stephens is driving down the road in her car and she has a glass of water. She has to stop very quickly. What happens (specifically!) to the water in the glass and why?
the water spills on the radio because it has inertia and wants to continue moving forward even though the car has stopped
what is inertia?
an object's tendency to resist any change in its motion
Why did the quarter fall into the cup when the index card was pulled away.
the quarter had Inertia
Which would have a greater acceleration, a small car or a large car, if the same force is applied?
a small car
While repairing the Hubble Telescope, which is in space, an astronaut turns a screwdriver clockwise. What direction will the astronaut turn?
counter-clockwise
Why does a marble on the floor slow down and eventually stop rolling if Newton's 1st Law says an object in motion stays in motion?
friction