How far does the water level drop in a cylindrical tank of internal diameter 35cm if 11 litres are drawn off

Answer 1

To find out how far the water level drops in the cylindrical tank, we need to calculate the volume of water that has been drawn off.

The volume of a cylinder is given by the formula V = πr^2h, where r is the radius of the cylinder and h is the height of the water.

Since the internal diameter of the tank is 35 cm, the radius (r) is half of that, which is 17.5 cm.

If 11 litres of water are drawn off, we know that 1 litre is equal to 1000 cm^3. Therefore, 11 litres is equal to 11,000 cm^3.

We can now plug in the values into the formula:

V = π(17.5)^2h = 11,000

We need to solve for h, the height of the water. First, calculate the volume on the left-hand side of the equation:

V = π(17.5)^2h = 961πh

Now, set this equal to 11,000:

961πh = 11,000

Divide both sides by 961π:

h = 11,000/(961π) ≈ 3.64 cm

Therefore, the water level drops by approximately 3.64 cm when 11 litres are drawn off from the cylindrical tank.