What is the average angular velocity?

AI Thread Summary
The discussion centers on calculating the average angular velocity for a rotating wheel using the given equation for angular displacement. The correct approach involves determining the initial and final angles at specific time intervals, t = 2.0 s and t = 3.3 s. The average angular velocity is then found by taking the change in angular displacement divided by the change in time. A participant initially miscalculated the values but later confirmed that the correct average angular velocity is 50 rad/s. The final resolution emphasizes the importance of accurately calculating the change in theta for the correct result.
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The angle through which a rotating wheel has turned in time t is given by \
theta = a t - b t^2+ c t^4, where theta is in radians and t in seconds.

What is the average angular velocity between t = 2.0 s and t =3.3 s?
If a = 9.0 rad/s, b = 16.0 rad/s^2, c = 1.6 rad/s^4

Homework Equations


d(theta)/dt = omega

omega average = change in theta / change in time

The Attempt at a Solution



omega =a-2bt+4ct^3

i got omega = 63.1 rad/s (omega =a-2bt+4ct^3 )

and 2nd time i got 19.0826 (change in theta / change in time)both is wrong when i put on the webs

can anyone help me please
 
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Since it's asking for an average, you should use the second equation you listed. I don't know how you got the answer you posted, but using the values you are given for t, find your initial and final thetas. Change in theta is final minus initial.

Write it all out...perhaps you put it into your calculator incorrectly?
 
change in theta / change in time

yep this work answer is 50

45-(-20) = 65/1.3 = 50

i put in 45-20 on my calc that why is wrong thank for help
 
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