If the diameter of a car tyre is 56 cm, then: How far does the car need to travel for the tyre Class 9
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If the diameter of a car tyre is 56 cm, then: How far does the car need to travel for the tyre Class 9
Question 1.
If the diameter of a car tyre is 56 cm, then:
How far does the car need to travel for the tyre to complete one revolution?
How many revolutions does the tyre make if the car travels 10 km? Class 9
Solution:
i. Diameter of tyre = 56 cm, radius = 28 cm
∵ Distance covered in one revolution = circumference of tyre
∴ C = 2πr
= 2 × $\frac{22}{7}$ × 28
= 22 × 8
= 176 cm
∴ Distance travelled by car in one revolution = 176 cm
ii. Distance covered by car = 10 km
= 10 × 1000 × 100
= 1000000 cm
Number of revolutions
$\begin{aligned} & =\frac{\text { total distance covered }}{\text { distance per revolution }} \\ & =\frac{1000000}{176}\end{aligned}$
= 5681.82
≈ 5682
∴ Number of revolutions ≈ 5682