The table describes the qualities of four objects.


Object Produces Light? Temperature (°C/°F)
a bouncing basketball no 20°C/68°F
the Sun's surface yes 5500°C/10,000°F
a lit light bulb yes 250°C/482°F
a fork sitting on a table no 15°C/59°F
Which of the following is most likely true?
A.
Small objects produce more light than larger objects.

B.
Large objects produce less heat than smaller objects.

C.
Objects that produce light energy often produce heat energy.

D.
Objects that do not produce light energy have high temperatures.

7 answers

The statement that is most likely true based on the information provided in the table is:

C. Objects that produce light energy often produce heat energy.

This is supported by the examples of the Sun and the lit light bulb, both of which produce light and are also at high temperatures. The other statements are not supported by the table data.

The diagram below shows two flasks of water, one with hot water and the other with room temperature water, which are connected by a conductive metal bar.

When initially set up, in which direction does the thermal energy between the flasks flow?
A.
Thermal energy flows from the flask on the left to the flask on the right.

B.
Thermal energy flows from the flask on the right to the flask on the left.

C.
Thermal energy does not flow between the two flasks.

D.
Thermal energy flows equally between the two flasks.

The correct answer is:

A. Thermal energy flows from the flask on the left to the flask on the right.

In this scenario, the flask with hot water (on the left) has a higher temperature compared to the flask with room temperature water (on the right). According to the second law of thermodynamics, thermal energy flows from the hotter object to the cooler one until thermal equilibrium is reached. Therefore, thermal energy will flow from the flask with hot water to the flask with room temperature water.

A piece of metal is heated and then submerged in cool water. Which statement below best describes what happens?
A.
The temperature of the water will decrease, while the temperature of the metal will increase.

B.
The temperature of the water will decrease and the temperature of the metal will also decrease.

C.
The temperature of the water will increase, while the temperature of the metal will decrease.

D.
The temperature of the water will increase and the temperature of the metal will also increase.

The correct answer is:

C. The temperature of the water will increase, while the temperature of the metal will decrease.

When the heated piece of metal is submerged in cool water, thermal energy transfers from the metal (which has a higher temperature) to the water (which has a lower temperature). As a result, the temperature of the metal will decrease while the temperature of the water will increase.

In an engine, fuel and oxygen chemically react and release energy. What happens to the energy NOT used by the engine?
A.
It has been destroyed.

B.
It is lost in the form of heat and sound.

C.
It remains stored in the chemical bonds of the fuel.

D.
It is converted into methane.

The correct answer is:

B. It is lost in the form of heat and sound.

In an engine, not all the energy released from the chemical reaction of fuel and oxygen is converted into useful work. A significant portion of the energy is typically lost as waste heat and sound energy, rather than being destroyed or remaining stored in any other form.