How Many Times A Wheel Of Radius 28 cm Must Rotate To Go 352 m?

20 times a wheel of radius 28 cm must rotate to go 352 m.

Importance Of SI System In Physics

The international system of units (SI) is the metric system which plays an important role in technological and scientific research and development. The SI unit is an international system of measurements that is used universally to minimise confusion with measuring units. The SI unit of length is the metre and it is denoted by the symbol ‘m’ whereas the centimetre is denoted by ‘cm’. In this article, we will also learn the relationship between metres and centimetres.

First of all, we have to find how many times that wheel rotates to cover the distance of 352m. As we know, the distance travelled by a wheel in one rotation is equal to its circumference. So, we can say that number of rotations = Distance covered/Circumference of the wheel.

Here, the radius of the wheel is r = 28 cm

To calculate the circumference of the wheel, we will use the formula Circumference = 2\pi r

Substituting the value of r in the above formula, we will get,

Circumference = 2×22/7×28 = 176cm

This is the value of the circumference of the wheel.

Now, distance travelled = 352 m = 35200 cm

So, the number of rotations = Total distance travelled/Circumference of the wheel

So, Number of rotations= 35200/176 = 200

So, we can say that the wheel must rotate 200 times to go 352 m.

Relationship Between Metre And Centimetre

To convert metres to centimetres, we need to multiply the number of metres by 100.

1 metre is 100 times of 1 centimetre.

So, 1 m = 100 cm.

For example: 15 metres = 15×100 = 1500 cm

To convert centimetres to metres, we need to multiply the centimetre value by 0.01 or divide the number of cm by 100.

So, in general 1 centimetre = 0.01 m = 1/100 m

Hence, we can say that 1 cm is the one-hundredth part of a metre.

Metres to centimetres conversion table:

• 1 metre = 100 centimetres

• 2 metres = 200 centimetres

• 10 metres = 1000 centimetres

• 20 metres = 2000 centimetres

• 0.1 metres = 10 centimetres

Examples

Here are a few examples which show how we can convert metres to centimetres and vice versa:

• Convert 40 cm into m.

40 cm = 40/100 = 0.4 m

Therefore, 40 cm is equal to 0.4 m.

• How many centimetres are there in 61 metres?

To solve this, we need to multiply the value in metres by the conversion factor ‘of 100’.

So, 61 metres = 61×100 = 6100 centimetres

Hence, we can say that 6100 centimetres are there in 61 metres.

• Convert 85 m into cm

85 m = 85×100 = 8500 cm

So, 85 m is equal to 8500 centimetres.