Definitions, etc.
Mass, time, and speed are examples of this type of measurement.
What is scalar?
An object moves a total of 5 meters east in 10 seconds then turns around and moves 5 meters west in 10 seconds. What is the average speed of this object?
0.5 m/s
20 N
A 15kg rock rolls with a speed of 3m/s. What is the momentum of the rock?
45kgm/s
A foot ball is kicked with an initial speed of 20m/s at an angle of 30 degrees from the ground. What is the x-component of the ball's velocity?
17.3m/s
What is work?
A bicycle moving at 3m/s west accelerates at a rate of 2m/s west for 4 seconds. What is the final speed of the bicycle?
11m/s
The centripetal force on a car going around a curve is 400N. If the speed of the car were cut in half, what would the centripetal force be?
100N
A force of 10N is applied to a cart over a distance of 10m. If this force is applied for 5s, what is the change of momentum of the cart?
50Ns
What is the power output of an electric motor that lifts a 2kg block 15m in 6s?
49W
If I want to find the change in an object's momentum, I'll need to calculate this quantity.
What is impulse?
A 10kg object is dropped from the top of a 100m tall building. How long does it take to reach the ground?
4.5s
A 20kg cart moving at 20m/s west collides with a 20kg ball moving at 45m/s east. Which has a greater inertia, the cart or the ball?
THEY HAVE THE SAME! INERTIA = MASS.
A 1,000kg car traveling at 5m/s is accelerated to a speed of 20m/s. What work was done on the car?
187,500J
Two 50kg students climb a flight of stairs 3m high. Student A climbs in 1.5s and student B takes 3s to reach the top. Which student does more work?
They both do the same amount of work.
A type of collision where the two objects begin as separate objects, but end up stuck together.
What is an inelastic collision?
A toy rocket is launched into the air with an initial speed of 19.6m/s. How long until it touches back down on the ground?
4s
Two 1kg rocks are places 1m apart in empty space. What is the force of gravity between the two rocks?
6.67 x 10-11N
A 60kg diver stands on a 80m cliff. When the diver steps off of the cliff, what will her speed be when she hits the water?
40m/s
How much work is done by normal force on a 5kg block being accelerated horizontally over a distance of 5m?
None. Vertical forces can't do work in a horizontal direction.
This is the ratio of friction force to normal force.
What is the coefficient of friction?
An alpaca travels 200m west, then 100m south. He then turns west for another 100m and again turns south for 300m. What is the alpaca's distance and displacement for the trip?
distance = 700m
displacement = 500m southwest
A 3kg toy car moves around a circular track once every 2 seconds.. If the track has a diameter of 2m, what is the centripetal force on the car?
29.6N
A 2kg ball with an initial speed of 10m/s east hits a wall and bounces back with a speed of 10m/s west. If the ball was in contact with the wall for 0.01s, what force did the wall exert on the ball?
4,000N
A 10kg object is on top of a 7m rough hill. When the object reaches the bottom of the hill, it has a speed of 7m/s. How much heat energy was created during this slide?
455J