Blackbody Radiation ; Planck's Quantum hypothesis

Based on the Wien's law, when the temperature increases, the phenomena that will be happen is...

• A. There is no change in the wavelength

• B. The wave length will be increase

• C. The wavelength will be decrease

• D.The frequency will be increase

• E. The frequency will be decrease

When the temperature of black body radiation is decrease, the maximum intensity of the radiation will be...

• A. Move to the longer wavelength

• B. Move to the higher frequency

• C. There is no change

• D. First it moves to the shorter wavelength and after that move back to the longer wavelength

• E. Depends on the condition

Two stars A and B emits the same amount of light. The wavelength that star A emits is longer than the wavelength that star B emits. What can you conclude from that explanation?

• A. The frequency of star A is higher than star B

• B. The frequency of star B is higher than star A

• C. The temperature of star A and star B is same

• D. The temperature of star A is higher than star B

• E. The temperature of star A is lower than star B

An iron rod is heated. The colors at different temperatures are noted. Which of the following colors shows that the iron rod is at the lowest temperature?

• red

• orange

• white

• blue

A black body is defined as a perfect absorber of radiations. It may or may not be a perfect emitter of radiations

• true

• false

A blackbody curve on a graph tells us how an object releases

• radio waves according to Planck's constant.

• light through a black hole's event horizon.

• radiation over different frequencies.

• heat over time.

Blackbody curves also tell astronomers about the ___ of an object (like a star).

• rotational energy

• temperature

• distance

• composition

What color would this object glow if it were heated to 5,000 K?

• Green

• Yellow

• Red

• Infrared

Choose the correct statement of an ideal blackbody

• Emits 100% of the light it generates, but cannot absorb its own radiation

• Absorbs half of the light incident upon it and emits half of the radiation it generates

• Absorbs all light incident on it, or emits all of the radiation it generates

• Absorbs 100% of the light incident upon it, but cannot emit light of its own

Which object has the highest temperature?

• A

• B

• C

• D

• F