The wheels of a car are of radius 40cm each, if the car is travelling at a speed of 66km/h, find the number of revolutions made by each wheel in 20 minutes

Answer: Each wheel makes 437.5 revolutions in 20 mins

Step-by-step explanation:

Circumference = 2πr

Given that the radius is 40 cm

Circumference = 2π (40) = 80π cm

Find the distance traveled in 20 mins

Speed = 66 km/h

1 hour = 66 km

Rewrite hour into min

60 min = 66 km

1 min = 66 : 60 = 1.1 km

Rewrite km in cm

1.1 km = 1.1 x 10,000 cm = 110,000 cm

Find the number of revolutions in 20 mins:

1 revolution = 80π cm

Number of revolution = 110,000 : 80π = 437.5