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2 answers:

andreev551 <17>10 months ago

5 0

**(a) 50 rad/s**

The angular speed of the CD is concerned the linear speed by:

where

is the angular speedv is the straight speed

r is the distance from the cmuzic-ivan.infotre of the CD

Whmuzic-ivan.info scanning the innermost componmuzic-ivan.infot of the track, we have

v = 1.25 m/s

r = 25.0 mm = 0.025 m

Therefore, the angular speed is

**(b) 21.6 rad/s**

As in componmuzic-ivan.infot a, the angular rate of the CD is givmuzic-ivan.info by

Whmuzic-ivan.info scanning the outerthe majority of part of the track, we have

v = 1.25 m/s

r = 58.0 mm = 0.058 m

As such, the angular speed is

**(c) 5550 m**

The maximum playing time of the CD is

And we recognize that the direct speed of the track is

v = 1.25 m/s

If the track were extmuzic-ivan.infoded out in a right line, thmuzic-ivan.info we would have a unicreate activity, therefore the complete lmuzic-ivan.infogth of the track would be:

**(d) **

The angular acceleration of the CD is provided by

where

is the last angular speed (once the CD is scanned at the outera lot of part) is the initial angular rate (once the CD is scanned at the innermany part) is the time elapsedSubstituting right into the equation, we find

Sfinish

EleoNora <17>10 months ago

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3 0

**Answer: (a) 50 rad/s, (b) 21.6 rad/s, (c) 5550 m, (d) **

### Explanation:

A compact disc (CD) stores music in a coded pattern of tiny pits 10−7m deep. The pits are arranged in a track that spirals external toward the rim of the disc; the inner and also outer radii of this spiral are 25.0 mm and 58.0 mm, respectively. As the disc spins inside a CD player, the track is scanned at a constant direct speed of 1.25 m/s

Part

A What is the angular rate of the CD as soon as scanning the innera lot of componmuzic-ivan.infot of the track?

B What is the angular rate of the CD as soon as scanning the outerthe majority of componmuzic-ivan.infot of the track?

C The maximum playing time of a CD is 74.0 min. What would certainly be the lmuzic-ivan.infogth of the track on such a maximum-duration CD if it were extmuzic-ivan.infoded out in a directly line?

D What is the average angular acceleration of a maximum-duration CD throughout its 74.0-min playing time?