Problem 10.17 A discus thrower starts from rest and begins to rotate with a constant angular acceleration of 1.6 rad/s². Part A How many revolutions does it take for the discus thrower's angular speed to reach 5.1 rad/s ? Express your answer using two significant figures. A0= ΕΡΕ ΑΣΦ Submit Request Answer Part B How much time does this take? Express your answer using two significant figures. ΜΕ ΑΣΦ t = Submit Request Answer Provide Feedback ? ? S revolutions 39 o

Human centrifuges are used to train military pilots and astronauts in preparation for high-g maneuvers. A trained, fit person wearing a g-suit can withstand accelerations up to about 9g (88.2 m/s2) without losing consciousness, (a) If a human centrifuge has a radius of 4.50 m, what angular speed results in a centripetal acceleration of 9g? (b) What linear speed would a person in the centrifuge have at this acceleration?

Olympic ice skaters are able to spin at about 5 rev/s. (a) What is their angular velocity in radians per second? (b) What is the centripetal acceleration of the skater's nose if it is 0.120 m from the axis of rotation? (c) An exceptional skater named Dick Button was able to spin much faster in the 1950s than anyone since—at about 9 rev/s. What was the centripetal acceleration of the tip of his nose, assuming it is at 0.120 m radius? (d) Comment on the magnitudes of the accelerations found. It is reputed that Button ruptured small blood vessels during his spins.

A wheel has a constant angular acceleration of 5.0rad/s2 . Starting from rest, it turns through 300 rad. (a) What is its final angular velocity? (b) How much time elapses while it turns through the 300 radians?