On an open-reel tape deck, the tape is being pulled past the playback head at a

Question

On an open-reel tape deck, the tape is being pulled past the playback head at a constant linear speed of 0.465 m/s.


(a) If the radius of the film taken up so far (as shown in the upper part of the drawing) is 0.0529 m, find the angular speed of the take-up reel.
___8.79____rad/s

(b) After 2.11 103 s, the take-up reel is almost full, as the lower part of the drawing indicates. The radius of film taken up so far is now 0.114 m. Find the average angular acceleration of the reel.
______ rad/s2

Specify whether the acceleration indicates an increasing or decreasing angular velocity.
=decreasing

I just need the answer to part b) please. can you show me how to work that part and give me the correct answer?

Explanation / Answer

a) Initial angular speed, 1 = v / r1                                           = 0.465 / 0.0529                                           = 8.79 rad/s Ans: Initial angular speed, 1 = 8.79 rad/s (b) Final angular speed, 2 = v / r2                                          = 0.465 / 0.114                                          = 4.07 rad/s Angular acceleration, = ( 2 - 1 ) / t                                          = ( 4.07 - 8.79 ) / 2.11 x 10^3                                          = - 2.24 x 10^-3 rad/s^2 Ans: Angular acceleration = - 2.24 x 10^-3 rad/s^2 The negative sign indicates decreasing angular velocity.

Related Questions

Navigate

• Browse (All)
• Browse O
• Subjects

---

---

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