Lesson video

Hi, I'm Miss Davies.

In this lesson, we're going to be working out the volume and surface area of a sphere.

To calculate the volume of a sphere, we're going to use the formula 4/3 pi r cubed.

In this example, the radius is five.

We type this into a calculator.

It gives us an answer of 523.

6 centimetres cubed.

To calculate the surface area of a sphere, we use the formula four pi r squared.

We know that the radius is five.

If we type this into our calculator, we get an answer of 314.

16 centimetres, correct to two decimal places.

Here are some questions for you to try.

Pause the video to complete your task, and resume once you're finished.

Here are the answers.

Here is a question for you to try.

Pause the video to complete your task, and resume once you're finished.

Here is the answer.

To work out the volume of a sphere with a radius of eight centimetres, you needed to calculate 4/3 multiplied by pi, multiplied by eight cubed.

This gives an answer of 2,145 centimetres cubed to the nearest integer.

Here are some questions for you to try.

Pause the video to complete your task, and resume once you're finished.

Here are the answers.

if the diameter of the sphere is 13 centimetres, this means that the radius is 6.

5 centimetres.

That's all for this lesson.

Thanks for watching.