Question

A car wheel has a radius of 35 cm.(a) What is the circumference of the wheel? Give your answer correct to 2 decimal places.(b) If the wheel rotates 100 000 times, how far does the car travel?

Answer 1

if radius (r)=35 cm

we know,
circumference of the wheel= 2 pi r
=2*22/7*35
= 220cm (it covers 220 cm in one rotation)

Now if the wheel rotates 100000 times,


it will travel = 220* 1000000
= 220000000 cm
= 220000000/100m
=2200000m

Answer 2

Step-by-step explanation

(a) The formula for the circumference of a circle is as follows:

`C=2\pi r`

Where r is the radius of the circle. So, we have:

`X=2\pi r=2\cdot3.1415\ldots\cdot35=219.9114\ldots\approx219.91`

So, the circumference is approximately 219.91 cm.

(b) Assuming the wheel is always in contact and every rotation make sthe exact same length of travel, every rotation will make the car travel approximately 219.91 cm.

If the wheel rotates 100,000 times, the car will travel 100,000 times as many, so it will travel:

`100,000\cdot219.91=21,991,000`

So, the car will travel approximately 21,991,000 cm which is equivalente to 219.91 km.

Answer

(a) the circumference is approximately 219.91 cm

(b) the car will travel approximately 21,991,000 cm or 219,91 km.