Question

The diameter of the driving wheel of a bus is 140 cm. How many revolutions per minute must the wheel make in order to keep a speed of 66 km per hour?

Answer 1

Answer:here is ur answer ....

Step-by-step explanation:

Answer 2

Answer:

Number of revolutions per min is 250.

Step-by-step explanation:

Given : The diameter of the driving wheel of a bus is 140 cm.

To find : How many revolutions per minute must the wheel make in order to keep a speed of 66 km per hour?

Solution :

Diameter of the wheel = 140 cm

Radius of the wheel is = 70 cm =0.70 m

The circumference of the wheel is

$C = 2\times \frac{22}{7}\times0.70 m \\C= 4.4 m$

Distance to be covered in 1 min. is

$D=\frac{(66 \times 1000)}{60}m \\D= 1100 m$

Circumference = No.of revolutions * Distance covered

$n=\frac{C}{D}$

$n=\frac{1100}{4.4}$

$n=250$

Number of revolutions per min is 250.