A wheel is rotating about an axis that is in the z-direction. The angular veloci

Question

A wheel is rotating about an axis that is in the z-direction. The angular velocity z is -6.00 rad/s at t = 0, increases linearly with time, and is +4.00 rad/s at t = 18.0 s . We have taken counterclockwise rotation to be positive.

A) Is the angular acceleration during this time interval positive or negative?

B) How long is the time interval during which the speed of the wheel is increasing?

C) How long is the time interval during which the speed of the wheel is decreasing?

D) What is the angular displacement of the wheel from t=0s to t=18.0s?

Explanation / Answer

A) angular acceleration = [4 - (-6)]/18 = 0.555 /s^2

Hence positive

B) time for which speed is increasing = [4-0]/0.555 = 7.272 sec

C) time for which speed is decreasing = [0- -6]/0.555 = 10.8108 sec

d) s = ut + 0.5at^2

= -6*18 +0.5*0.625*18*18 = -6.75 rad

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.