
A watering can sprinkles water at the rate of , The can has a diameter of and is initially filled to its full capacity.

What is the height of water in the can after it is used for minutes? Show your work. (Note: Take )


Important Questions on Surface Areas and Volumes
Two people have an equal amount of moulding clay. They make different solids of the same circular radius out of it- cylinder and hemisphere.
State true or false for the given statements and justify your answer.
- Simran said, "The curved surface area of the cylinder is larger."
- Manoj said, "Both the solids have the same curved surface area."

A bird feeder tube has a diameter of and height of . The tube has circular openings of diameter each for the birds to eat from. The tube can hold a maximum of of bird food.
If the birds eat an average of of food per hour, what will be the height of the food in the tube after hours? Show your work. (Note: Take )

A semi-circular waffle sheet of radius is folded into an ice-cream cone as shown below.
Due to overlap while folding, the radius of the base of the cone is of what it would be without overlap. Find the approximate volume of the cone. Show your work. (Note: Take )

A cloche is used to cover dishes before serving. Shown below is a hemispherical glass cloche of radius . Kanan wants to use it to cover a cylindrical cake of volume .
Find one set of values of radius and height of the cake, such that the cloche does not touch the cake when covered. Show your steps. (Note: Take .)

Shown below is a solid made of a cone, a cylinder and a hemisphere.
Prove that the total volume of the solid is twice the volume of the cylinder.

Dinesh is building a green house in his farm as shown below. The base of the greenhouse is circular having a diameter of and it has a hemispherical dome on top.
How much will it cost him to cover the walls and top of the greenhouse with transparent plastic, if the plastic sheet costs per ? Show your steps. (Note: Take )

Shown below is a cake that Subodh is baking for his brother's birthday. The cake is tall and has radius of . He wants to surprise his brother by filling gems inside the cake. In order to do that, he removes a cylindrical portion of cake out of the centre as shown. The piece that is removed is tall.
If the cake weighs per and the weight of the cake that is left after removing the central portion is , find the radius of the central portion that is cut. Show your steps.

Shown below is a triangular prism and a cylinder.
On filling the cylinder with water and completely submerging the prism inside the filled cylinder, some water was forced to overflow out of the cylinder. When the prism was removed again, it was noticed that the cylinder had exactly of its water remaining.
If the volume of the cylinder is litres, what is the volume of the prism? Show your steps and give valid reason.
