1. At the Olympics, a discobolus “discus thrower" starting from rest, spins up to an angular velocity of 20 rad/s in 0.7 s. (Assume perfectly circular motion) (a) What is the angular acceleration during this spin up? Once released, the discus flies off with a tangential velocity of 18 m/s at an angle 30° above the horizontal. (b) What is the approximate length of the discus players arm (from the center of the discus player to the point where he held the discus in his hand)? (c) How high does the discus go above the initial release point?

1. At the Olympics, a discobolus “discus thrower" starting from rest, spins up to an angular velocity of 20 rad/s in 0.7 s. (Assume perfectly circular motion) (a) What is the angular acceleration during this spin up? Once released, the discus flies off with a tangential velocity of 18 m/s at an angle 30° above the horizontal. (b) What is the approximate length of the discus players arm (from the center of the discus player to the point where he held the discus in his hand)? (c) How high does the discus go above the initial release point?

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter9: Momentum And Its Conservation

Section: Chapter Questions

Problem 1STP

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