The diameter of a cycle wheel is 126 cm. A cyclist takes $16\frac{1}{2}$ minutes to reach the destination at a speed of 72 km/hr. How many revolutions will the wheel make during the journey?(Take $\pi = \frac{22}{7}$)
Answer & explanation
Correct answer: option 1
We know that,
Circumference of circle = 2πr = Distance covered by wheel in one revolution
Distance covered by Cyclist in 16.5 minutes with speed of 72 km/hr = 72 × \(\frac{100000}{60}\) × \(\frac{33}{2}\) = 1980000 cm
Distance covered by wheel in 1 revolution = 126 × \(\frac{22}{7}\) = 396
Number of revolutions = \(\frac{1980000}{396}\) = 5000