Net Force
If the net force applied on an object is equal to zero, we say that a force is _________________.
Balanced
Newton's 3rd Law states: Every action has an ___________ and ___________ reaction.
Equal and Opposite
Is magnetism a contact or non-contact force?
Non-Contact
A marathon runner keeps a consistent pace of 9 minute miles.
Does this best describe speed, velocity or acceleration?
Speed
True or false: The reaction force of our bottle rockets was the rocket moving upwards
True. The action force was the pressure inside the bottle forcing the water downward. The reaction was the rocket launching into the air.
Grant and Rhys are making a snowman and they need to roll a large snowball several yards away. If they both push it to the right with 50 N of force, which direction will the snowball move?
To the right
What is Newton's 2nd Law of Motion?
Force = Mass x Acceleration
How do contact forces and non-contact forces differ?
A contact force requires two objects to touch in order for them to work, a non-contact force does not require any objects to touch for them to work
A cyclist slows her pace when she rounds a corner.
Does this best describe speed, velocity or acceleration?
Acceleration
What is the unit of force?
Newtons (N)
If a forces are unbalanced, the net force can be any amount other than ______________.
Zero
Mrs. Rushia was driving on the highway when a small rock hit her car. The rock went flying away, but left a big crack in the windshield. Which of Newton's Laws can explain this?
Newton's 3rd Law
If Mr. Donahue goes skydiving, name one contact and one non-contact force he will experience
Air Resistance and Gravity
In order for a rocket to escape earth's atmosphere, it needs to travel upward at 7 miles per second.
Does this best describe speed, velocity or acceleration?
Velocity
If the mass of an object is 25kg and the acceleration of the object is 6m/s squared, what is the force of the object?
150N. (25x6=125)
Mrs. Oliveira is trying to move a 400kg refrigerator. She pushes it, and Mrs. Beyer helps her by pulling it. Mrs. Oliveira pushes with 200 N and Mrs. Beyer pulls with 40 N. What is the net force applied upon the refrigerator?
240 N
A football player with a smaller mass and lean muscle is more likely to be a quarterback (lots of running) than a lineman (less running, more blocking). Which of Newton's Laws supports this statement?
Newton's Second Law
Black holes are incredibly massive objects in space. What force allows their pull to be so great that not even light can escape?
Gravity
Give an example of an object that is changing its speed, velocity and its acceleration all at once
Example: A car slows to a stop at a stop light and turns right.
Gravity is the force of _________________ between two objects.
Attraction
Bill and Bob are moving a heavy dresser. Bill exerts 150 newtons of force to the left, while Bob is exerting 120 newtons of force to the right. What is the Net Force applied to the dresser, and which direction will it move?
Bill and Bob are not very smart. They are both exerting a lot of force, but in opposite directions. The Net force is 30 N to the left.
150-120 =30
What is inertia?
The tendency for an object to resist a change in motion
Which opposing contact force is greatly reduced by the design of a bullet train, powered by strong repelling magnets?
Friction. The train does not have much contact with the track, reducing friction. The repelling magnets allow the train to "hover" on the track.
A rocket travels too close to a nearby planet and gets pulled into orbit by the planet's gravity.
Explain what would happen to the rocket's speed, acceleration and velocity
The rocket's velocity would change and therefore accelerate (at least).
As the rocket was pulled in by gravity, its direction would change as it moved toward the planet, thus affecting both its velocity and its acceleration. Its speed may also change, but we do not have enough information here to know.
What is another word for air resistance, commonly used when discussing planes or rockets?
Drag