Physics Unit 7b Centripetal Force & Acceleration & Torque Test

Which of the "Parameter - SI Unit" combinations listed below are correct and proper for our study in this physics unit?

• torque - newton meters

• velocity - meters per second

• period - minutes

• acceleration - meters squared per second

• force - newtons

The combined mass of a race car and its driver is 600 kg. Travelling at constant speed, the car completes one lap around a circular track of radius 160 meters in 0.6 minutes. What is the magnitude of the centripetal acceleration of the car? Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 0.17 m/sec²

• 4.9 m/sec²

• 78 m/sec²

• 100 m/sec²

An airplane is circling in the sky at a speed of 150 meters/second. The airplane describes a circle of radius 20 kilometers. For a passenger of mass 80 kg inside this airplane, calculate the centripetal force acting on her. Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 0.60 N

• 90 N

• 600 N

• 1200 N

Find the centripetal force of a 7.0 kilogram object traveling around a circle with a radius of 9.8 feet if the tangential speed of the mass is 3.0 meters per second. Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 9 N

• 63 N

• 7 N

• 21 N

Child no. 1 weighing 310 N and child no. 2 weighing 250 N were playing on a seesaw. If the 1st child sits 2.2 m from the fulcrum, how far from the fulcrum must the 2nd child sit to balance the seesaw? Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 0.75 m

• 2.7 m

• 1.8 m

• 1 m

Calculate the amount of centripetal force it takes for a softball pitcher to rotate a ball with a velocity of 3 meters per second if the ball weighs .12 kilograms and her arm is .65 meters long. Be sure to show all your work on your worksheet in order to get any credit for this problem.

• .38

• 1.23

• .55

• 1.66 N

A test car moves at a constant speed around a circular track. If the car is 48.2 m from the track's center and has a centripetal acceleration of 8.05 m/s², what is the car's tangential speed? Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 19.7 m/s

• 5.99 m/s

• 0.17 m/s

• 388.01 m/s

What is the counterclockwise torque acting on this crane? Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 80,000 Nm

• 100,000 Nm

• 120,000 Nm

• 140,000 Nm

Two masses of 10.0 kilograms and 6.0 kilograms are hung from massless strings at the end of a light rod. The rod is virtually weightless. A pivot (fulcrum) is placed off center and the system is free to rotate. If the 6.0 kilogram mass is 4.0 meters away from the pivot, how far away is the 10.0 kilogram mass assuming that the system is not rotating? Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 0.42 m

• 2.4 m

• 4.8 m

• 4.2 m

Two masses of mass 10.0 and 6.0 kg are hung from massless strings at the end of a light rod. The rod is virtually weightless. A pivot (fulcrum) is placed off center and the system is free to rotate. If the string supporting the 10 kg mass is cut, what is the net torque of the system? Be sure to show all your work on your worksheet in order to get any credit for this problem.

• 24 Nm

• 60 Nm

• 240 Nm

• 480 Nm