Give Some Applications Of Convections?

Following are some of the application of convection

-Household hot-water systems:  the working principle of the household hot water system which is based on the convection in liquids is as follows:

Water is heated in the boiler by the gas burner. The hot water expands and becomes less dense. Hence, it rises and flows into the upper half of the cylinder.                     
To replace the hot water, cold water from the cistern falls into the lower half of the cylinder and then into the boiler due to pressure difference. The overflow pipe is attached to the cylinder just in case the temperature of the water becomes too high and causes a large expansion of the hot water.

The hot water tap which is led from the overflow pipe must be lower than the cistern so that the pressure difference between the cistern and the tap causes the water to flow out of the tap

-Electric kettles: the heating coil of an electric kettle is placed at the bottom of the kettle. When the power is switched on, the water near the heating coil gets heated up. It expands and becomes less dense. The heated water therefore rises while the cooler regions in the upper part of the body of water descend to replace the heated water.