I'm really bad at physics, so any help is appreciated. Here is the question-
A rotating wheel moving at an unknown initial angular velocity requires 3.00 s of constant angular acceleration to rotate its next 37.0 revolutions. Its angular velocity at the end of the 3.00 s interval is 98.0 rad/s.
a.) Find the average angular speed during the interval.
I got ω=154.99 rad/s. Is this correct? Probably not
b.) Use ωaverage to find the initial angular velocity.
c.) What is the constant angular acceleration (in rad/s²) of the wheel?
Thanks in advance.
A rotating wheel moving at an unknown initial angular velocity requires 3.00 s of constant angular acceleration to rotate its next 37.0 revolutions. Its angular velocity at the end of the 3.00 s interval is 98.0 rad/s.
a.) Find the average angular speed during the interval.
I got ω=154.99 rad/s. Is this correct? Probably not
b.) Use ωaverage to find the initial angular velocity.
c.) What is the constant angular acceleration (in rad/s²) of the wheel?
Thanks in advance.
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Average angular speed = (total angle)/time
It moved 37 * 2pi radians in a time of 3 seconds. So its average angular speed is 37 * 2pi/3.
As a sanity check, you have a number which is bigger than both the starting and the ending angular speeds. That can't possibly be the average for something which was steadily accelerating. It has to be less than 98 rad/sec since it was getting faster all the time. It was below 98 rad/sec the entire time, so it can't average out to 155.
For constant acceleration, the average is halfway between the initial and final velocities. Use that to solve for the initial velocity.
Acceleration is change in velocity/time. Subtract those two velocities and divide by the time.
It moved 37 * 2pi radians in a time of 3 seconds. So its average angular speed is 37 * 2pi/3.
As a sanity check, you have a number which is bigger than both the starting and the ending angular speeds. That can't possibly be the average for something which was steadily accelerating. It has to be less than 98 rad/sec since it was getting faster all the time. It was below 98 rad/sec the entire time, so it can't average out to 155.
For constant acceleration, the average is halfway between the initial and final velocities. Use that to solve for the initial velocity.
Acceleration is change in velocity/time. Subtract those two velocities and divide by the time.
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