Physics · Thermal Properties Of Matter · NEET
No. Temperature tells you how hot a body is (its degree of hotness). Heat is the energy that moves from a hot body to a cold body when their temperatures are different. Two cups can be at the same temperature (say 60 C) but a big cup holds more heat energy than a small cup, because it has more mass.
A body does not store heat. Heat is energy in transit; it only exists while it is flowing due to a temperature difference. What a body has is internal energy and a temperature. Once flow stops (temperatures equal), we no longer call it heat. So the phrase 'heat contained in a body' is wrong; the correct idea is internal energy.
Heat flows, temperature does not. Heat always moves from the higher-temperature body to the lower-temperature body until both reach the same temperature (thermal equilibrium). Temperature is just the property that decides the direction of this flow, like water level decides which way water flows between two connected tanks.
A spark can be at a very high temperature (thousands of kelvin) but has almost no mass, so it carries very little heat energy. A bucket of warm water is at a lower temperature but has huge mass, so it holds much more heat. This shows temperature and heat are different: high temperature does not always mean large heat.
Heat is energy, so its SI unit is the joule (J); an older unit is the calorie (1 cal = 4.186 J). Temperature has the SI unit kelvin (K); it is also measured in degree Celsius (C). Remember: joule for heat, kelvin for temperature. Mixing these units is a common NEET mistake.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Heat is the form of energy transferred between a body and its surroundings by virtue of a temperature difference. Temperature is the quantity that measures the degree of hotness or coldness of a body.
No. If two bodies are at the same temperature, there is no temperature difference, so no net heat flows between them. They are said to be in thermal equilibrium.
Temperature is a scalar quantity. It has magnitude only and no direction. Heat is also a scalar (a form of energy).
Because heat only exists while energy is moving from one body to another due to a temperature difference. Once the flow stops, that energy becomes part of the body's internal energy and is no longer called heat.
Temperature is measured with a thermometer. Heat (energy exchanged) is measured indirectly using a calorimeter and the formula Q = m c delta T, not read off a single scale.
