The radius of the wheel of a vehicle is 70 cm. The wheel makes 10 revolutions in 5 seconds. The speed of the vehicle is?
Correct Answer: 31.68 km/hr.
Explanation:
Circumference = 2πr
= 2 x (22 / 7) x 70 cm
= 440 cm Distance travelled in 10 revolutions = 440 x 10 cm
= 4400 cm
= 44 m ∴ Speed = distance / time
= 44 / 5 m/sec
= (44 / 5) x (18 / 5) km/hr
= 31.68 km/hr
