Friction
Gravity
Newtons Laws
Force body diagrams
100
True or False.
A bike on grass is a form of friction?
True
100
What direction dos gravity act?
Downwards
Towards earth surface
100
Which of Newtons laws best fits the situation of a rocket ship propelling itself into outer space?
Newtons 3rd Law
Thrusters push down into the ground which exerts a force upwards for the ship!
100
What happens when an object has a net force not equal to zero?
It will ACCELERATE!!!
(not accepting "It will move" or "It will have a velocity")
200
Which is a form of decreasing friction intentionally?
A. Putting snow tires on a car when the road is icy
B. Oil on a a squeaky door hinge
C. Wearing cleats in field sports
D. None of the above
B
200
1) How does your weight on the moon compare to your weight on earth? Why?
2) How does your mass on the moon compare to your mass on earth? Why?
1) Weight on moon is less then that on earth because the gravitational force is stronger on earth since its mass is very large
2) Mass is the same wherever you are! Mass is the amount of substance within a body or certain area, that will not change on earth or on the moon
200
True or False: An object in motion will stay in motion.
FALSE....unless acted upon by an outside force
200
If an object accelerates to the Southwest....
1) Is the HR positive or negative?
2) Is the VR positive or negative
1) negative
2) negative
300
What is the definition of friction? What does it do to the objects?
When two objects physically touch and rub against one other opposing its motion
300
What is the measurement of the force of gravity on an object?
Weight
300
Which of Newton's laws states: That an object at rest will stay at rest and an object in motion will stay in motion at a constant velocity, unless acted upon by an unbalanced force.
Newtons 1st Law
300
If an object has zero net force acting upon it, it will .......
YOU NEED BOTH ANSWERS
1) move with a constant velocity
2) not move with any velocity
400
True or False.
Using snow tires on an icy road is an example of increasing friction.
True
400
What is the value for the acceleration due to gravity (with correct units)
9.81 m/s^2 or 9.8m/s^2
400
F=?
And what are the units for ALL parts of the equation
F=ma
N=(kg)(m/s^2)
400
Solve for the HR and VR for each one
1) HR: 0N VR:-5N
2) HR: 0N VR: 0N
3) HR: 0N VR:-3N
4) HR: 2N VR: 2N
500
In what directions does the frictional force act in....
1) Car moving North
2) Man free falling while skydiving
3) Car slowing down to the right
4) Sliding your hand up a wall
1) South
2) Up
3) Left
4) Down
500
What is the velocity of a human that has been in free fall for 4.7 seconds?
46.11m/s
(9.81m/s^2)(4.7s)
500
List all three Newtons laws of motion, describe what it is, AND give me one example for each
Lots of examples...
500
List all 5 forces and their correct definitions
Applied- a push or pull force you exert onto another object
Normal- a reactive force that acts perpendicular to the surface (human stands on ground, Fn is upwards)
Gravitational- Downward pulling force from one massive object to a smaller object (earth to human)
Friction- Two objects rub against one another and opposes motion
Tension- found in string when holding an object or pulling an object from one location to another