A racing car on a flat circular track needs friction between the tires and the track to maintain its circular motion. How much more friction is required for twice the speed?

Astronauts in the International Space Station must work out every day to counteract the effects of weightlessness. Researchers have investigated if riding a stationary bicycle while experiencing artificial gravity from a rotating platform gives any additional cardiovascular benefit. What frequency of rotation, in rpm, is required to give an acceleration of 1.4g to an astronaut’s feet, if her feet are 1.1 m from the platform’s rotational axis?

The following data measures a spinning mass at different angular speeds and the radial force (centripetal force) required to maintain its circular motion.  The mass always spins at a radius of: R = 5.14 cm   RPS Tangential Velocity (m/s) Force (N) 8.600   24.89 8.234   22.83 7.820   20.38 7.272   17.93 5.457   10.58 5.300   9.31 4.912   8.13 4.682   7.15 4.197   6.17 3.996   5.39 3.710   4.90 3.647   4.31 Convert from angular frequency to tangential speed

It has been suggested that rotating cylinders about 10.5 mi long and 6.32 mi in diameter be placed in space and used as colonies. What angular speed must such a cylinder have so that the centripetal acceleration at its surface equals the free-fall acceleration on Earth? rad/s =

On a carnival ride, you stand next to a wall of a circular drum which spins around the center. When drum is spinning fast enough the floor drops away and you remain stuck to the wall and do not slide down to the floor until the drum slows down some. Assume a rider has a mass of 55.0 kg, and the drum has a radius of 6.00 m. The average linear speed that a rider is traveling with around the drum is 7.80 m/s. What is the normal force that the drum is exerting on the rider to keep her from sliding down to the floor?

A child is standing on a merry-go-round (u - 16) with a radius of 2 meters. What is the fastest that can he be spun while only using the friction from his feet to stay on? 157 mis 244 m/s 3.14 m/s 177 ms

You have a horizontal grindstone (a disk) that is 87 kg, has a 0.31 m radius, is turning at 94 rpm (in the positive direction), and you press a steel axe against the edge with a force of 23 N in the radial direction. The kinetic coefficient of friction between steel and stone is 0.20. What is the number of turns, N, that the stone will make before coming to rest?

A 83-kg pilot in training sits in a centrifuge that spins his seat around a central axis. When the seat is moving in its circular path at a speed of 3.0 m/s, he feels a 585-N force pressing against his back (the seat faces the axis). What is the radius of the centrifuge?

t has been suggested that rotating cylinders about 16.0 mi long and 5.06 mi in diameter be placed in space and used as colonies. What angular speed must such a cylinder have so that the centripetal acceleration at its surface equals the free-fall acceleration on Earth?

Starting from rest, a basketball rolls from the top to the bottom of a hill, reaching a translational speed of 6.3 m/s. What is the height of the hill?(Ignore frictional losses) 2.0 m 3.4 m 4.1 m 6.1 m