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.

During a very quick stop, a car deceleraes at 7.00 m/s^2.a. What is the angular acceleration of its 0.280-m-radius tires, assuming they do not slip on the pavement? Answer: 25.0 rad/sec^2b. How many revolutions do the tires make before coming to rest, given their initial angular velocity is 95.0 rad/s? Answer: 28.7 turnsc. How long does the car take to stop completely? 3.8 secd. What distance does the car travel in this time?e. What was the car’s initial velocity?f. Do the values obtained seem reasonable, considering that this stop happens very quickly? Note: I only need subpart d. to f. Answers