Question

The diameter of the wheel of a car is 56 cm. Calculate : The speed of the car, in km per hour, if its wheel makes 75 revolutions in 1 minute​

Answer 1

Step-by-step explanation:

We have

Diameter of the wheel = 56 cm.

Radius of the wheel.

2

Diameter

=

2

56

=28 cm.

Circumfrence of the wheel = 2πr

2×

7

22

×28

= 2×22×4

= 8×22

= 1.76 cm.

Given that, = 1.76 mtr.

Number of revolutions in 1 minute = 750

Distance covered = 750×1.76

= 13.92 km.

Distance covered in 60 minute = 13.92×60

= 835.2 km/h

Answer 2

Diameter of the wheel = 56 cm.

Radius of the wheel = Diameter/2 = 56/2 = 28 cm.

Circumfrence of the wheel = 2πr

2×22/7 × 28

= 2×22×4

= 8×22

= 1.76 cm.

Given that,  = 1.76 m

Number of revolutions in 1 minute  = 75

Distance covered = 75×1.76 = 1.392 km.

Distance covered in 60 minute = 1.392×60 = 83.52 km/h