Question

In cities, water supply from an overhead tank to the houses is done due to:
$\left( A \right)$ difference in pressure
$\left( B \right)$ gravitational force
$\left( C \right)$ decrease of friction in pipes
$\left( D \right)$ flow of liquid

Answer 1

Hint: The position of the water is from where it will flow downwards. Work should be done on water against the force of gravity to store water at a height in a tank. The energy stored in a body due to its position is potential energy. Using the above statements determine the cause of the above scenario.

Complete solution:
Water in the overhead tank tends to fall down due to its weight. The gravitational force of attraction between the earth and the earth is the force applied to the water stored. The potential energy stored in water is used still today to get water in our taps from tanks kept on the roof of our house. This is used in a fountain by letting the water fall from a height which could convert the stored potential energy into kinetic energy.
Water in the tank in a tank has higher gravitational potential compared to water that flows out of the taps in the houses. Water moves due to the decrease in gravitational potential energy of water flowing out of taps. The flowing out of taps, the water is supplied by the gravitational force on the water.

Note: The energy stored in a body due to its position is potential energy. The potential energy stored in water is used still today to get water in our taps from tanks kept on the roof of our house. Work should be done on water against the force of gravity to store water at a height in a tank. The flowing out of taps, the water is supplied by the gravitational force on the water.