Question

Question #27b73

Answer 1

(a) `40pi" cm"`
(b) `2.34xx10^3cm cdot s^-1`, rounded to two decimal places.
(c) `117.29radian cdot s^-1`, rounded to two decimal places.
(d) `0.05s`, rounded to two decimal places.

Explanation:

(a) The tip of fan moves distance equal to one circumference of the circle made by the tip.

`:.` Distance moved by the tip in one revolution`=2pir`
`=2xxpixx20.0 =40pi" cm"`
(d) Time period `T` of motion is time taken for one revolution.

`:.` Fan makes `1120rp m`
`=>T=60/1120=0.05s`, rounded to two decimal places.
(c) Angular acceleration `omega=(2pi)/T=117.29radian cdot s^-1`, rounded to two decimal places.
(b) For circular motion, tip's speed `v=romega`
`=>v=20.0xx117.29=2345.72cm cdot s^-1`