Question

The wheel of a car is of radius 40 cm each. If the speed of a car is 22m/s then no. Of rev made by each wheel in 20 sec

Answer 1

Step-by-step explanation:

Find the circumference of the wheel

/* Formula */

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 1000 m = 1100 m

1100 m = 1100 x 100 cm = 110 000 cm

Find the number of revolutions in 20 mins:

1 revolution = 80π cm

Number of revolution = 110 000 ÷ 80π = 437.5

Answer: Each wheel makes 437.5 revolutions in 20 mins