1 ) A wheel is making 240 rpm and after 30 sec and after 30 sec it is running at 150 rpm .(adsbygoogle = window.adsbygoogle || []).push({});

A) Find the time elapse before it stops if the retardation is uniform ?

B) Find the time elapse after it stops if the retardation is uniform ?

my answer :

w0 = 240 rpm = 8Pi rad/s

w = 240 rpm = 5pi rad/s

t = 30

------

w = w0 + at

a = -0.1Pi

time elapse before it stops

w = w0 + at

5pi = 8Pi - 0.1Pi (t)

t = 94.4 s

time elapse after it stops

w = w0 + at

5pi = 0 - 0.1Pi (t)

t = 50 s

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# Homework Help: A wheel is making 240 rpm and after 30 sec and after 30 sec

**Physics Forums | Science Articles, Homework Help, Discussion**