Physics 7.1 Quiz (3/4/21)

[Word Problem] A car on a roller coaster loaded with passengers has a mass of 2.0 x 10^3 kg. At the lowest point of the track, the radius of curvature of the track is 24 m and the roller car has a tangential speed of 17 m/s. What is the centripetal acceleration of the roller car at the lowest point on the track?

Answer: 12m/s^2 (rounded down) Solution: Centripetal Acceleration = v^2/r v = 17^2, r = 24 17^2/24 = 12.041 m/s^2 -> 12m/s^2

[Word Problem] A child rides a bicycle in a circular path with a radius of 2.0m. The tangential speed of the bicycle is 2.0m/s. The combined mass of the bicycle and the child is 43kg. What is the magnitude of the bicycle's centripetal acceleration?

Answer: 2.0 m/s^2 Solution: Centripetal Acceleration = Velocity^2/Radius V = 2^2, R = 2 4/2 = 2

[Word Problem] A 35kg child moves with uniform circular motion while riding a horse on a carousel. The horse is 3.2m from the carousel's axis of rotation and has a tangential speed of 2.6m/s. What is the centripetal force on the child?

Answer: 74 N (rounded up) Solution: Find Centripetal Acceleration first = v^2/r v = 2.6^2, r = 3.2 2.6^2/3.2 = 2.1125 Then, find Centripetal Force = m • centripetal acceleration m = 35, a(c) = 2.1125 35 • 2.1125 = 73.937 N -> 74N

The centripetal force on an object in circular motion is

in the plane of the object's motion and perpendicular to the tangential speed

When a car makes a sharp left turn, what causes the passengers to move toward the right side of the car?

inertia

When an object is moving with uniform circular motion, the centripetal acceleration of the object...

is directed toward the center of motion

What term describes a change in the speed of an object in circular motion?

tangential acceleration

Which of the following quantities measures the ability of a force to rotate or accelerate an object around an axis?

torque