Question

All BUT one factor will increase the work output of a machine and decrease the amount of thermal energy created and released. That isA) develop new and more efficient fuels.
B) add a lubricant, such as oil, to the machine.
C) increase the friction the machine encounters.
D) improve the design of the machine to decrease friction.

Answer 1

I would say C because extra friction would make the machine work more and therefore create more heat.

Answer 2

Option (c) is correct.

Friction is a force that opposes the motion of an object. Friction is a non conservative force. So the work done against the friction is dissipated as heat and gets wasted.That decreases the work output of a machine.We can increase the work output of a machine by using efficient fuels,using lubricants etc. we can also improve the design of the machine to increase the work output. Thus increasing friction will not increase the work output but will decrease it.