Heat lets us feel the temperature of a given body. Picture this, if an individual touch is a hot cup of tea, their immediate reaction is to get their hands off that cup. It happens because their hand feels the heat of the water in the cup. However, that doesn’t mean that the human body does not produce heat. It just means that the heat of the cup had a higher temperature as compared to the temperature of the human body.
A person can relate heat with temperature. However, both the term share different facts and characteristics. While the term heat has the opposite term cold, the term temperature does not. It is a common misconception of considering heat equivalent to temperature. It is a common practice because they let a person feel and experience the heat energy that compels them to think that heat and temperature are the same.
Even though the two terms heat and temperature more or less mean the same, they differ in certain viewpoints. Apart from this, the two terms are calculated and measured differently according to the guidelines of physics. Keep reading to find out the details that make them different from each other. But first, let us get into some introductory information.
How to understand the difference between heat and temperature?
Heat is referred to as the total energy due to the motion of the molecules in a substance. It means that the movement of the molecules generates a form of energy which is called heat.
On the other hand, temperature is defined as the measure of the average energy of a substance made by the motion of its molecules. It implies that temperature refers to the average energy produced by the activity of the particles of a substance.
It is observed that heat is dependent on certain factors like the speed of the molecules, the size of the particles, the number of the molecules, and many other physical factors. At the same time, the temperature is independent of any physical characteristics.
For example, a person can imagine a big hot bowl of soup and a small bowl of soup. The observable characteristic of both the bowls is that they are at the same temperature. However, the quantity of soup in the big bowl is more than the quantity of the soup in the smaller one. It makes a person imagine that the number of particles present in the bigger bowl is more than the number of particles present in the smaller bowl.
It explains that even though both the bowls or at the same temperature, there is a difference in the heat around them, i.e., the bigger bowl (which has more soup) has now thermal energy compared to the smaller bowl. Hence, More heat is evolved from the bigger bowl though it has the same temperature as the smaller bowl of soup.
The heat energy evolved from a body or during a process is termed heat. It is generally observed that when an object is at high temperatures or is considered to be immensely hot, it is supposed to possess an exceptional amount of heat energy.
Similarly, when an object is at lower temperatures or is considered to be very cold, it is supposed to possess less heat energy. In scientific terms, a body is always supposed to possess some heat energy, even if it is in a negative form. It even implies that the objects are very cold. Keep in mind that every object is made above atoms and molecules, and when they collide, they produce heat energy.
What do you understand about the transmission of heat?
Heat is a form of energy that can be transformed and transmitted from one object to another. As the law of conservation of energy states that energy can neither be created nor be destroyed, heat energy also follows the same rule. It means that a body always possesses heat in rest or a body in motion, irrespective of the temperatures that they are in.
By obeying the law of conservation of energy, heat energy can also be transformed from one form of energy to another. Nevertheless, heat is capable of transferring from one object to another object in three different ways –
Conduction refers to heat transmission when the object is in a solid-state. In solid substances, the transmission of heat takes place by conduction. Except for mercury, all liquids and gases are considered poor conductors of heat.
It is observed that when a solid body is heated, the molecules gain kinetic energy and begin to vibrate as a result of increased energy. The transmission of heat by conduction occurs when the heat energy travels from one particle two another particle through a solid body.
This movement of heat results in the vibration of the particles against each other. The more the collision of the particles inside a solid body, the better conductor of heat it is. A conductor is set to be good when its particles are close enough to collide with each other to produce sufficient energy.
Convection refers to the transmission of heat in liquids and gases. It is termed how heat energy flows through the molecules in a liquid and gas. During the heat transmission by convection, the liquid or gas particles are heated slowly because of the space between their particles.
Liquids and gases have more space between their particles than solid substances. And hence, they take longer to heat up. One can demonstrate it by an easy example.
Suppose a person starts heating a pan of water. He observes that the water near the flame gets heated up quickly compared to the water far from the heat flame or on the edge of the pan. The heat inside any liquid is transmitted across its particles through convection.
The transmission of heat by radiation is different from that of conduction and convection. It is because the transmission of heat by radiation only takes place when there is no medium for the heat to travel. An appropriate example of heat transmission by radiation is the heat energy that we get from the sun. Because of the absence of a medium, the heat energy from the sun travels to the surface of the earth through radiation.
Radiated heat can travel in vacuum or empty spaces without the help of a medium. Moreover, this transmission of heat across a vacuum is transmitted in the form of electromagnetic energy, which has a similar way of transmission to light waves.
Now that we have an idea about the concept of heat, it is time to understand more about temperature. A comparison between the two terms will help us understand the difference between them.
Temperature is the physical quality of a substance that tells us whether the body is hot or cold. While heat energy produces kinetic energy in the molecules of a substance, the temperature is the average of that kinetic energy associated with motion.
But how do we know the intensity of how cold or how hot a body is? An individual can effectively understand the difference between hot and cold; they have to first study temperature.
If a person has a fever, the doctor is more likely to check their temperature with the help of a thermometer. A thermometer is a device that helps to measure the temperature of a body. It is interesting to know that while a temperature can be 50° Celsius, it can also be -50° Celsius.
The difference between heat and temperature
|It is denoted by the symbol Q.||It is denoted by the symbol T.|
|It is a form of energy.||It is not a form of energy.|
|It is the energy possessed by the body.||It is the hotness or coldness of the body.|
|Joules is the SI unit of heat.||Kelvin is the SI unit of temperature.|
|Heat energy depends on the mass, temperature, and material of the substance.||Temperature of a substance depends on the average kinetic energy produced by its molecules.|
|Heat energy is measured by the principle of calorimetry.||A thermometer is used to measure temperature.|
From the above explanations, it is clear that heat and temperature are two different entities. While heat is a form of energy, temperature is not. The temperature of an object cannot tell the amount of heat energy that it holds.
The comparison between the two terms can help an individual understand the important concepts of physics for their competitive exams like NEET and JEE. The small details and concentration on different characteristics can help an individual make out the difference between heat and temperature. Although a person can deem them alike, they are different.
1. Can you measure heat? How?
Yes, it is possible to measure the amount of heat energy possessed by a body. The principle of calorimetry is used to determine the measurement of heat produced. Apart from this, a person can also study and calculate the amount of heat involved, released, and required through the principles of calorimetry.
2. What is the unit for heat?
Heat is a form of energy that is defined as The total energy that comes from the motion of the molecules of a body. It is the energy possessed or stored inside a body. It is measured by the principle of calorimetry and has an SI unit of Joules (J).
3. What is the sI unit of temperature?
Temperature is the physical quality of a substance that tells us whether the body is hot or cold. While heat energy produces kinetic energy in the molecules of a substance, the temperature is the average of that kinetic energy associated with motion. The SI unit of temperature is Kelvin (K).
4. The term Celsius belongs to which category, heat or temperature?
The Celsius scale determines the measure of temperature. Along with the Fahrenheit scale and the Kelvin scale, the Celsius scale is also used to measure the temperature of a body. So, the term Celsius deals with the calculations and measurement of temperature.