The diameter of a wheel is 70 cm. It completes 600 revolutions in 1 minute. The speed, in km/h, of the vehicle is:(Take $π =\frac{22}{7}$)
Answer & explanation
Correct answer: option 2
We know that,
Circumference of a circle = 2 π r
Given,
The diameter of wheel = 70cm
So, the Radius of wheel, r = 35 cm
Revolutions in 1 minute = 600
Circumference of the wheel = 2 × \(\frac{22}{7}\)× 35 = 220 cm
Distance covered in 1 revolution = 220 cm
So, distance covered in 1 minute = 220 × 600 = 132000 cm
= 13200cm = 1.32 km
Distance covered in 1 minute = 1.32 km
Hence, distance covered in 1 hr = 1.32 × 60 = 79.2 km