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Flashcards in Exam 3 Deck (11)
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1

Motion or kinetic energy of the molecules in a substance

Heat

2

What has more energy—a cold or a hot object?

Hot object—it has more kinetic energy

3

Thermal energy flows spontaneously (without external assistance) from a higher-temperature object to a lower temperature object. It will not spontaneously flow the other way

The second law of thermodynamics

4

The total energy of an isolated system is conserved. Energy may be transferred from one part of the system to another, and energy may be transformed from one form to another, including thermal energy, but the total value of the energy is conserved

First law of thermodynamics

5

Any device that uses thermal energy to do
work is called

Heat engine

6

In one cycle of operation a heat engine consumes 1500 J of thermal energy and performs 400 J of work. What is the amount of energy that is exhausted in each cycle? What is the efficiency of this engine?

1100 J
0.27 or 27%

7

A substance in which electric charge can flow readily

Conductor

8

A substance in which electric charge does not flow easily

Insulator

9

The flow of charged particles

Electric current

10

A current that reverses its direction as time goes by

Alternating current

11

A time-changing magnetic field produces a time-changing electric field

Faraday’s Law of Induction