Momentum
A 200 kg car is driving at 25 m/s. What is their momentum?
50,000 kg m s-1
A car is going around a curve. What force is responsible for its centripetal acceleration?
Force of friction
You push on a door that is 1 m wide at the hinge with a force of 5 N. What is the net torque on the door?
Zero!
A merry-go-round is spinning at 170 rpm. It weighs 500 kg and has a radius of 5 m. What is the angular momentum of the merry-go-round? (note: Moment of inertia for a disk is 1/2MR^2)
111,250 kg m^2 s^-1
A 5 kg block slides at 2 m/s when it hits a stationary block that has a mass of 2 kg. The two blocks travel together. What velocity do they travel at?
+1.4 m/s
A car (1500 kg) is going around a curve of r=40 m. If the coefficient of static friction is 0.6, what is the fastest they can go around the curve?
15.3 m/s
You push on a door in the center with a force of 5 N. At the same time, your friend pushes on the edge of the door from the other side with a force of 2 N. What is the net torque on the door. (see slides for image)
T net = -0.5 Nm
If a disk of 200 kg with a radius of 3 m is placed at the center of the merry-go-round from 100, what will the angular velocity be?
15.56 rad/s
Two people standing on a frictionless surface and they push off of each other. The first person has a mass of 100 kg and travels at 5 m/s in the negative direction. If the second person has a mass of 6.6 m/s, what is their speed after the collision?
A 2 kg ball is on the end of a string. It swings in circles while sitting on a frictionless table at 2 rpm. If the string is 1 m long, what is the force of tension on the string?
A 5 m plank is balanced at its center. A 6 kg object is then placed on one end. Where should a 20 kg object be placed to balance the plank?
0.75 m from center on the opposite side from the first object.
If I am standing on a turntable with my arms outstretched to 0.5 m (moment of inertia. = 3 kg m^2). I have a 5 kg dumbell in each hand and am spinning at 3.14 rad/s. If I bring my arms in to 0.2 m from my body, how fast will I spin?
A pool ball (0.15 kg) travels at +2 m/s when it hits a stationary pool ball (0.17 kg). After the collision, the second pool ball travels at 3 m/s. What happens to the first pool ball.
Travels in the negative direction at 1.4 m/s