Question 20 (1 point)
When energy is conserved or transferred, some energy becomes unavailable to do useful work. What happened to the unavailable energy?
a
It is conducted.
b
It is completely destroyed.
c
It is given off as microwaves.
d
It is given off as heat.
d
It is given off as heat.
d
It is given off as heat.
The correct answer is d) It is given off as heat.
When energy is conserved or transferred, some of it inevitably gets converted into a form that is not usable to perform useful work. This conversion typically happens due to the natural processes of friction and other inefficiencies.
In most cases, the unavailable energy is given off in the form of heat. Heat energy is the random motion of molecules and atoms, and it cannot be easily harnessed to perform work. For example, when mechanical energy is converted into heat through friction, the heat generated is often lost to the surroundings and cannot be utilized further.
It is important to note that the energy itself is not destroyed. According to the law of conservation of energy, energy cannot be created or destroyed, but it can only change its form. In this case, the energy is transformed into heat, which is a less organized and less useful form of energy for performing work.