4400 Higher November 2005 Paper 3 Q18
18
Diagram NOT accurately drawn
The outer diameter of a hollow spherical ball is 10 cm.
The ball is made from rubber which is 0.4 cm thick.
Calculate the volume of rubber needed to make the ball.
Give your answer correct to 3 significant figures.
(4)
| Scheme | Marks |
|---|---|
| \(\dfrac{4\pi}{3} \times 5^3 - \dfrac{4\pi}{3} \times 4.6^3\) 523.59… − 407.72… | M1 B1 B1 |
| 116 | A1 |
| (4) | |
| (4 marks) |
Notes
M1: for \(\dfrac{4\pi}{3}R^3 - \dfrac{4\pi}{3}r^3\)
B1: \(R = 5\) used correctly
B1: \(r = 4.6\) used
A1: for 116 or better (115.878…)
ft from \(r\) if \(4 < r < 5\)