Explanation:

Explanation:
Heat Transfer: The movement of heat from a warmer object to a colder one – when two substances at different temperatures are mixed together, heat flows from the warmer body to the cooler body until they reach the same temperature (Zeroth Law of Thermodynamics – Thermal Equilibrium). Part of the heat lost by the warmer body is transferred to the cooler body and part is lost to the surrounding object or the air.

Convection is the process of heat transfer by the bulk movement of molecules within fluids such as gases and liquids. The initial heat transfer between the object and the fluid takes place through conduction, but the bulk heat transfer happens due to the motion of the fluid.

• Convection is the process of heat transfer in fluids by the actual motion of matter.
• It happens in liquids and gases.
• It may be natural or forced.
• It involves a bulk transfer of portions of the fluid.

How is Heat Transferred through Convection? When a fluid is heated from below, thermal expansion takes place. The lower layers of the fluid, which are hotter, become less dense. We know that colder fluid is denser. Due to buoyancy, the less dense, hotter part of the fluid rises up. And the colder, denser fluid replaces it. This process is repeated when this part also gets heated and rises up to be replaced by the colder upper layer. This is how the heat is transferred through convection. Types of Convection: There are two types of convection, and they are:

1. Natural convection: When convection takes place due to buoyant force as there is a difference in densities caused by the difference in temperatures it is known as natural convection.Examples of natural convection are oceanic winds.
2. Forced convection: When external sources such as fans and pumps are used for creating induced convection, it is known as forced convection. Examples of forced convection are using water heaters or geysers for instant heating of water and using a fan on a hot summer day.

Conduction is the transfer of energy in the form of heat or electricity from one atom to another within an object by direct contact. Conduction occurs in solids, liquids, and gases. However, solids transfer energy most efficiently since the molecules in solids are most tightly packed, and the molecules are closer together, as shown in this figure. For liquids and gases, the density of the particles are generally lower than those of solids and the particles are farther apart, so the energy transfer is less efficient. There are two main types of conduction:
1. Conduction of heat occurs when molecules increase in temperature; they vibrate, and this vibration and movement passes the heat energy to the surrounding molecules. Some examples of conduction of heat are accidentally touching a hot pot, or when a heating pad is applied to you directly and warms your muscles.
2. Conduction of electricity occurs due to the movement of electrically charged particles through a medium. This movement can result in an electric current, which may be carried by electrons or ions. An example of electrical conduction is when you accidentally get electrocuted when you touch a live wire because your body contains water, which is a conductor of electricity. Another example is when electricity passes through wires, which are conductors, so we can watch TV or use a computer.