Physic- A hammer thrower rotates

2008-12-15 2:32 am
A hammer thrower rotates faster and faster until he releases the hammer. the last revolution takes place at a constant angular speed and last 4.0s. During the last revolution , the hammer of mass 6.0kg is at a distance of 2.0m from the central vertical axis of rotation through the man's body. Find the magnitude of the force exerted by the man's hands on the hammer. F=?

回答 (1)

2008-12-15 3:01 am
✔ 最佳答案
The force exerted by the man's hand on the hammer accounts for the centripetal force of the hammer.

Now, mass of the hammer, m = 6.0 kg

Radius of the circular path, r = 2.0 m

Angular frequency, ω = 2π / T

= 2π / 4.0

= 1.57 rads-1

Now, we have

F = mrω2

F = (6.0)(2.0)(1.57)2

F = 29.6 N
參考: Myself~~~


收錄日期: 2021-04-25 16:00:29
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081214000051KK01652

檢視 Wayback Machine 備份