Question

The wheel of an engine of 300 cm in circumference makes 10 revolutions in 6 seconds. What is the speed of the wheel (in km/h)?

• A. 18
• B. 20
• C. 27
• D. 36

Answer 1

The correct option is A

18

Circumference means one revolution.
Therefore, distance covered in 10 revolutions $=300\times 10$
= 30 m
i.e., 30 metre in 6 seconds.
$\therefore$ Speed of wheel $=\frac{30}{6}m/s=5m/s\therefore 5m/s=5\times \frac{18}{5}=18km/h$