Question

The wheels of a car are made of diameter 80 cm each how many complete revolutions does each will make internet when the car is travelling at the speed of 66 km per hour

Answer 1

Answer:

Number of revolutions is 4375.

Step-by-step explanation:

We know that diameter is 80 cm, then the radius is $\frac{80}{2}$ = 40 cm.

From speed = $\frac{distance}{time}$ when can get the distance each wheel made in 10 minutes.

First we need to convert minutes in hours, 10 minutes is equal to $\frac{1}{6}$ hour.

Then:

66 = $\frac{distance}{[tex]\frac{1}{6}$}[/tex]

distance = 66 x $\frac{1}{6}$ = 11 kms.

Now,

number of revolution = $\frac{total distance}{distance in 1 revolution}$

Since distance in 1 revolution is equal to 2 x π x radius, which is equal to 2 x 40 x π, equal to 80π cm.

We need to change the unit of the total distance to centimeters, so we have 11 kms = 1100000 cms

Thus:

number of revolution = $\frac{1100000}{80π}$ = 4375 revolutions.

Hence the number of revolutions made in 10 minutes when the car is at 66 km per hour is 4375.