Physics

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The angular velocity of a process control motor is (21−12t2) rad/s, where t is in seconds.

A)At what time does the motor reverse direction?

I got 6.5s

B) Through what angle does the motor turn between t =0 s and the instant at which it reverses direction?

Can anyone do B

  • Physics -

    a. 21-12t^2=0 or t= sqrt21/12 which is not 6.5 seconds

    b. rework a.

    displacement=INT (21-12t^2) dt from o to T above

  • Physics -

    Actually it is 6.5 seconds... I worked it and that's what mastering chemistry said was correct also

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