Review EG 10 - 11 | Take the Quiz

In a closed system, what will occur if Object A and Object B have different temperatures?

Energy transfer

Increase in energy

Increase in temperature

Change in temperature

Three cups with the same amount of water are in a room with an ambient temperature of 25°C. Cups A, B and C have initial temperatures of 60°C, 50°C and 40°C, respectively. Which cup will most quickly reach its final temperature?

Cup A

Cup B

Cup C

All cups will reach their final temperature at the same time

For thermal equilibrium to happen, what must be the condition of System A, System B and System C?

Systems A, B, and C must have the same temperature

System A and System B must have the same temperature

System B and System C must have the same temperature

System C and System A must have the same temperature

A heat engine, in each cycle, does positive work and loses energy as heat, with no heat energy input. Which law of thermodynamics does the heat engine violate?

Zeroth Law of Thermodynamics

First Law of Thermodynamics

Second Law of Thermodynamics

Third Law of Thermodynamics

Which of the following is an engine that violates the second law of thermodynamics?

An engine that is less efficient than a Carnot engine.

An engine that changes all of its mechanical work into heat.

An engine that operates in a cycle with two isotherms and two adiabats.

An engine that changes all the heat from the source to mechanical energy.

How does a refrigerator exhaust heat to a warmer place?

The vaporization of the refrigerant liquid absorbs energy.

The motor converts electrical energy into thermal energy.

The inside of the refrigerator is properly insulated from heat.

The compression of the refrigeration gas into liquid gives off heat.

A heat engine has a hot reservoir of 600 K and a sink of 300 K. What is its ideal efficiency?

0.5

0.8

Which of the following statements BEST describes how a geothermal power plant acts like a heat engine?

It converts heat energy from water into potential energy.

It directly uses heat from within Earth and converts it into electricity.

It uses steam turbines to convert electricity into mechanical energy.

It burns fossil fuel in the ground and uses its heat to generate electricity.

Which of the following is NOT a factor why machines can never be 100% efficient?

Heat loss

Time

Resistance

Friction

If 1 kWh is priced at 9 Php, and a family consumed 120 kWh of electricity for the past month. How much will they pay for it?

Php 1,080

Php 1,000

Php 13.33

Php 500