The diameter of the wheel of a vehicle is 5 metre. It makes 7 revolutions per…
2024
The diameter of the wheel of a vehicle is 5 metre. It makes 7 revolutions per 9 seconds. What is speed of the vehicle in km/h?
- A.
60 km/h
- B.
65 km/h
- C.
44 km/h
- D.
50 km/h
Attempted by 302 students.
Show answer & explanation
Correct answer: C
Solution: Calculate the speed step by step.
Circumference of the wheel = π × diameter = (22/7) × 5 = 110/7 m.
Distance covered in 7 revolutions = 7 × 110/7 = 110 m (this is the distance covered in 9 seconds).
Speed in m/s = distance ÷ time = 110 ÷ 9 = 110/9 ≈ 12.22 m/s.
Convert m/s to km/h by multiplying by 18/5: (110/9) × (18/5) = 44 km/h.
Answer: 44 km/h