In order to calculate the amount of energy required, we must first check the latent heat of vaporization of water from literature. The latent heat of vaporization of any substance is the amount of energy required per unit mass to convert that substance from a solid to a liquid. For water this is 2,260 J/g. We now use the formula:
Energy = mass * latent heat
Q = 50 * 2,260
Q = 113,000 J
113,000 Joules of heat energy are required.
Explanation:
- A thermometer does measure the temperature of a body and not the heat. It is known that temperature is a measure of average kinetic energy.
Therefore, the statement a thermometer measures the average kinetic energy of a substance is correct.
- Heat is a form of energy as it can make a colder substance become hot and it moves from one place to another. Thus, the statement heat is a form of energy is correct.
- Also, heat flows from hotter substance to colder substance. Hence, the statement heat flows from a colder substance to a hotter substance is correct.
- Convection is a property of fluids or gases which makes less denser (hot) material to rise and more denser (colder) material to sink.
Therefore, the statement convection occurs only in liquids and gases is correct.
- All substances radiate heat is an incorrect statement. For example, a thermos bottle does not radiate heat.
- Temperature of our body is about 98.4 degree celsius and hence we can conclude that the statement our body temperature is always equal to the temperature around us is incorrect.
Answer:
The atoms of the system with higher temperature will gain the heat energy and the vibration of these atoms will increase. The atoms or molecules on the system with lower temperature have lower temperature and are not vibrating. ... So, we can say that heat always flows from higher temperature to a lower temperature.
True, because for example you are on a bus and you want to know if you are moving or not so you look at a house which doesn't move and stays stationary.