First Law of Thermodynamics

The first law of thermodynamics states that the change in the internal energy of a system is equal to the difference in energy transferred to or from the system as heat and

• mass

• work done

• force

• pressure

The first law of thermodynamics is a restatement of the

• Zeroth Law of Thermodynamics

• Law of Heat Addition

• Principle of Entropy

• Law of Conservation of Energy

Tags

NGSS.HS-PS3-2

When applying the first law of thermodynamics to a system, when is heat a positive quantity?

• when the system does work

• when the system has work done on it

• when the system absorbs heat

• when the system loses heat

• when no work is done either on the system or by the system

A pump full of compressed gas is allowed to expand and 80 kJ of work is done by the gas on an object in the lab. At the same time, the gas is warmed by the addition of 100 J of heat energy. If the initial internal energy of the gas is 500 kJ, calculate the final internal energy.

• 500 kJ

• 80 kJ

• 100 kJ

• 520 kJ

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

Neither mass or energy can be created or destroyed.

• First Law of Thermodynamics

• Second Law of Thermodynamics

• Murphy's Law

• DeWeese's Law

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-7

What does the First Law of Thermodynamics state about energy in a closed system?

• Energy can be created but not destroyed.

• Energy can neither be created nor destroyed, only transformed.

• Energy can be destroyed but not created.

• Energy can be both created and destroyed.

Which of the following scenarios is an example of the First Law of Thermodynamics in action?

• A car engine burning fuel to move the car forward.

• A ball rolling down a hill without friction.

• A light bulb being turned off.

• A perfectly insulated room that neither gains nor loses heat.

Tags

NGSS.HS-PS3-4

A foam cup is filled with hot water and allowed to cool while being stirred by a paddlewheel. Initially the water has an internal energy of 200 kJ, and while cooling it loses 150 kJ of heat. The paddlewheel does 25 kJ of work on the water.

Calculate the change in internal energy of the water.

• -150 kJ

• -125 kJ

• 75 kJ

• 200 KJ

Tags

NGSS.HS-PS3-1

A foam cup is filled with hot water and allowed to cool while being stirred by a paddlewheel. Initially the water has an internal energy of 200 kJ, and while cooling it loses 150 kJ of heat. The paddlewheel does 25 kJ of work on the water.

Calculate the final internal energy of the water.

• -150 kJ

• -125 kJ

• 75 kJ

• 200 KJ

Tags

NGSS.HS-PS3-1

Calculate the change in internal energy of a system that does 1.20 MJ of work (out) while 4.8 MJ of heat transfer occurs (out) to the environment. Assume no other changes (such as temperature or by the addition of fuel) take place.

• -3.6 MJ

• 3.6 MJ

• -6.0 MJ

• 6.0 MJ

Tags

NGSS.HS-PS3-1