1.6 Absorbing Radiation (Infrared & Black Body)

Question 1

For a cup of tea, more energy will be ___________ than ____________

Answer 1

emitted, absorbed

Question 2

For an ice cube, less energy will be ____________ than ___________

Answer 2

emitted, absorbed

Question 3

On a graph for the emitted radiation, does intensity go on the y or x axis?

Answer 3

y axis

Question 4

On a graph for the emitted radiation, does wavelength go on the y or x axis?

Answer 4

x axis

Question 5

The wavelength of radiation the object emits most of it called the p___________ ______________

Answer 5

Principal wavelength

Question 6

What is meant by ‘intensity’ on the graph of emitted radiation?

Answer 6

How much energy each wavelength of the emitted radiation transfers to a given area in a certain amount of time

Question 7

Does the intensity increase more for shorter wavelength or longer wavelength? and why

Answer 7

The intensity increases more for shorter wavelength than longer wavelengths because shorter wavelength of EM radiation transfer more energy. This causes the principal wavelength to decrease

Question 8

What happens to the graph’s curve when an object gets hotter?

Answer 8

The principal wavelength gets shorter and the intensity-wavelength distribution becomes less symmetrical

Question 9

What is the principal frequency?

Answer 9

The principal frequency is the frequency of radiation that an object emits the most of. The principal frequency increases as the temperature of an object increases

Question 10

The overall temperature of the Earth depends on the amount of radiation it ______, _______ and ______

Answer 10

reflects, absorbs, emits

Question 11

How does radiation also affect the Earth’s temperature? (4)

Answer 11

• During the day, lots of EM radiation is transferred to the Earth from the Sun. The atmosphere allows some of it to pass through to be absorbed by the Earth’s surface. This warms it and causes an increase in the local temperature
• At night, less EM radiation is being absorbed than is being emitted, causing a decrease in the local temperature
• Overall, the temperature of the Earth stays fairly constant
• Changes to the atmosphere can cause a change to the Earth’s overall temperature

Question 12

What type of radiation does an object at room temperature mostly emit?

Answer 12

Infrared radiation