Question

A car travels at a constant speed of 45 km per hour for 5 min each wheel has a radius of 25 centimeters calculate the number of complete revolutions that the wheel makes in 5 min

Answer 1

477.47 revolutions

Explanation:

From the information given:

The formula for calculating the circumference = 2π r

Given that the radius of each wheel = 25 centimeter

Then, the circumference = 2 π (25)

= 50π cm

The distance traveled in 5 minutes is as follows:

Given that:

The speed = 45 km/ hour

i.e.

1 hour = 45 km

In an hour, we have 60 minutes

So, 60 minutes = 45 km

1 minute = 45/60 = 0.75 km

To cm;

0.75 km = (0.75 × 1000) m = 750 m

750 m = 750 × 100 = 75,000 cm

∴

The number of revolution in 5 minutes sInce 1 revolution = 50π cm is:

= 75,000 cm/ 50π cm

= 477.47 revolutions in 5 minutes