A bucket is raised from a well by means of a rope which is wound round a wheel of diameter 77 cm. Given that the bucket ascends in 1 minute 28 seconds with a uniform speed of 1.1 m/sec, calculate the number of complete revolutions the wheel makes in raising the bucket.

Explanation

Diameter =77 cm

Radius =`D/2​=77/2 ​cm =77/200 ​m`

Speed =1.1 m/s

Time =1 min 28 sec=88 sec

Distance can be completed as `S×T=1.1×88=96.8 m`

Circumference `=2×pi×r=2×22/7​×77/200​=2.42 m`

No. of Revolution = `"Distance"/" Circumference" ​=96.8/2.42​=40`

∴ Number of revolution = 40