Question

The wheels of a car are of radius 40 cm each. If the car is travelling at a speed of 66
km per hour, find the number of revolutions made by each wheel in 20 minutes.
.
.
.
. solve the question step by step ​

Answer 1

Answer:

Radius (r)= 40cm

Circumference of wheel = 2 × pi × r = 2 × 22/7 × 40

= 1760/7 cm

Distance covered = Speed × Time = 66km/h × 20min

= (66km/h × 1/3 h)

= 22km

= 2200000 cm

1 revolution = Circumference of wheel = 1760/7

Distance covered = Number of revolutions × Circumference

Let N = Number of revolutions

=>

$2200000 = n \times \frac{1760}{7}$

=>

$n = \frac{2200000 \times 7}{1760}$

=> n = 8750

Hence, number of revolutions made by each wheel is 8750