# Definition Of Heat

## Definition Of Heat

Heat is a form of energy which transfers from hot body to a cold body.

• Transfer of heat from an object depends on surrounding object temperature
• "A" is an object with a temperature of 800C, and "B" is an object with a temperature of 400 and both the objects are in contact with each other. Then heat transfers from A to B till both temperatures are equal (600C).
• When both the temperatures are equal heat stops flowing. Heat transformation will not take place
• Example of Heat: A very hot cup of coffee is placed on the table. After certain time we notice that both the cup and coffee are cold, because the surrounding room temperature is only 260C, Hence the heat flows from hot cup (900C) to the surroundings. If you wait patiently for long duration of time the coffee will be cooled to room temperature.
Example of Heat: Consider a glass of fruit juice taken out freshly from a refrigerator. The glass and Juice will be very cool (around 4 to 50C) If you place the same on a table for long duration of time, it can be noticed that the glass and the juice are not that cool as they both absorb the heat from the surroundings (room temperature around 260C). Thus heat always flows from hot body to cold body.
• An object cools down by transformation of heat.
• And another object warms up by the same transformation of heat.

• Heat transforms in solids through conduction
• Heat transforms in liquids through convection
• Heat transforms in gases through radiation

Related Terms: Temperature | Specific heat | conduction | convection | radiation