FOOD TECHNOLOGY

Detailed explanation-1: -Macaroni rising and falling in a pot of boiling water is due to convection. As due to convection, macaroni goes up with heat current and when it reaches the top of pot it is constrained by lid and gravitational force takes it down.

Detailed explanation-2: -The movement of steam or the motion of boiling water in a pot are also examples of convection.

Detailed explanation-3: -Convection can be observed when you boil water. The hot water increases in thermal and molecular kinetic energy and rises as it becomes less dense. The water transfers heat to the surrounding water and air and eventually sinks. This creates the circular current that can be observed in a pot of boiling water.