A wheel of a car has a radius 21 cm. If it is rotating at 800 RPM, what is the speed of the car?

Expert Answers

An illustration of the letter 'A' in a speech bubbles

The radius of the wheel is 21 cm. When the wheel rotates once, the distance covered by the car is 2*pi*21.

As the wheel rotates at 800 RPM, it covers a distance equal to 2*pi*21*800 cm per minute.

The distance covered in one hour is 2*pi*21*800*60/100 m

=> 20160*pi m

=> 20.16*pi km

=> 63.33 km (approximately)

The required speed of the car is 20.16*pi or 63.33 km/hr.

Approved by eNotes Editorial Team

Posted on

Soaring plane image

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial