Find The Energy Turned Into Heat
Energy is a very powerful and useful concept in physics and when it comes to understanding the relationship between energy and heat, the knowledge can go a long way. In this article, we’ll have a look at how energy is converted into heat, and the equation used for calculating the amount of energy required for this conversion.
Energy and Heat
As stated earlier, energy and heat are closely related concepts. Heat is basically a form of energy that is transferred from one object to another due to a temperature difference. Heat is produced as a result of work and can be just as easily converted back into work, given the right conditions. The amount of heat produced is directly proportional to the amount of work done.
Heat can be converted to work either through the process of combustion or through the passage of electricity. In other words, when work is done, some of the energy is converted to heat. This is why an engine needs cooling – to regulate the amount of energy that is converted to heat.
Calculating Amount of Heat Produced
To calculate the amount of heat produced, the equation Q = mcΔT is used, where Q is the heat energy transferred (in joules) and m is the mass of the object (in kg). ΔT is the change in temperature (in Kelvin). This equation can be used to determine the amount of energy required in order to raise the temperature of a given object.
For example, if an object has a mass of 2 kg and a temperature of 50°C, and we want to raise its temperature to 80°C, we can use the equation to calculate how much energy is required to do this. Using the equation, we get: Q = 2 x 4.184 x (80 – 50) = 437.44 J. Thus, the energy required to raise the temperature of the object by 30°C is 437.44 joules.
Specific and Latent Heat
Apart from the amount of energy required to raise the temperature of an object, there are two other types of heat transfer. These are called specific heat and latent heat. Specific heat is the amount of energy required to increase the temperature of a unit mass of a substance by one degree. Latent heat is the heat energy required to change the state of a substance, such as from liquid to gas.
For example, if we want to increase the temperature of 1 kg of water by 1°C, then we need to supply 4.184 J of energy. This is the specific heat capacity of water. Similarly, if we want to convert 1 kg of water from a liquid to a gas, then we need to supply 2,260 J of energy – this is the latent heat of water.
In summary, energy and heat are closely related concepts. Heat is a form of energy that is produced when work is done, and it can be converted back into work given the right conditions. To calculate the amount of energy required for this conversion, the equation Q = mcΔT can be used. Apart from the energy required to raise the temperature of an object, there are two other types of heat transfer – specific and latent heat.