What is the difference between a scalar and a vector?
Vector has magnitude and direction, scalar has just magnitude
100
What is inertia?
A property of matter--the resistance something has to its change in motion
100
How much work to you do on a stationary wall if you push it with a force of 100 N for 30 seconds?
None! Wall doesn't move!
100
In order to have momentum, what does an object have to have?
Velocity!
100
If the mass of an object is doubled, what happens to its gravitational attraction?
It is also doubled
200
If you push on a wall with a force of 30 N, how much force does the wall exert back on you?
30 N
200
What causes accelerations?
Unbalanced forces
200
If you push an object twice as far while applying the same force, you do ______ as much work
twice
200
What causes a change in momentum?
An impulse (Ft)
200
Which way is centripetal force pointed?
Towards the center of the circle
300
If velocity is negative and acceleration is positive, is the object speeding up or slowing down?
Slowing down
300
What is the difference between mass and weight?
Weight has to do with the acceleration of gravity--its a force. Mass of something never changes.
300
What does an object need in order to have kinetic energy?
Needs to be moving
300
What is the difference between an elastic collision and an inelastic collision?
Elastic: objects bounce off one another
Inelastic: objects stick together
300
Where are the horses that go the fastest located on the merry-go-round?
closest to the edge
400
Which would fall to the ground with the slowest acceleration: a tennis ball or a bowling ball?
Same acceleration! 9.8 m/s^2. They have different FORCES though, because their masses are different.
400
What does the free body diagram of a package being pushed across a floor (with friction present) and accelerating?
Normal force up, Force of gravity down, applied force right (bigger vector), friction force left (smaller vector)
400
A ball has the most potential energy at the ____ of a hill, and the most kinetic energy at the ____ of a hill. Directly in the middle of the hill, the potential energy and kinetic energy are _____.
top, bottom, equal
400
How do airbags help the passengers of a car?
They increase the time of impact, which decreases the force of impact (impulse doesn't change!!)
400
Would an object on the moon weigh more or less than it does on Earth?
Less
500
What is the slope of a line on a position vs. time graph?
velocity
500
What does the free body diagram of a hockey puck sliding across the frictionless ice AFTER it has been hit look like?
Normal force up force of gravity down only!
500
Billy lifts a 50N box 1 m onto a truck in 2 seconds, while Bobby lifts 50 1N boxes onto the same truck in 25 seconds. How does the work done and power exerted compare between Billy and Bobby?
They do the same amount of work but Billy exerts more power because he does it in less time.
500
If a huge truck and a mini cooper traveling at the same speed have a head-on collision, which will experience the greatest change in velocity?
The mini cooper
500
Planet X has an acceleration of gravity equal to 12 m/s^2. If the radius of the planet were to double without changing the mass, what would the new acceleration of gravity be?