Complete
1. …………………………is an electromagnetic radiation that you can see.
2. Electromagnetic waves radiate ………………………… and
………………………… fields in all directions from a source.
3. Energy carried by electromagnetic waves are called
………………………….
4. Energy in electromagnetic waves is related to its……………………….
While energy in mechanical waves is related to its…………………….
5. Wavelengths of light waves range from …………to ……….nanometers.
6. …………………………. of light is the person’s perception of intensity.
7. The …………………………. of the wave is related to the measured
brightness.
8. …………………………. is a material that allows almost all of the light
striking through which objects can be seen clearly.
9. ………………………….is a material that allows most of the light that
strikes it to pass through, but through which objects appear blurry.
10.………………………….is a material through which light does not pass.
Essay
1. Mention three facts about electromagnetic waves.
…………………………………………………………………………………
…………………………………………………………………………………
…………………………………………………………………………………
2. Differentiate between the energy in mechanical and electromagnetic waves.
…………………………………………………………………………………
…………………………………………………………………………………
…………………………………………………………………………………
3. List the factors affecting brightness/intensity of light.
i) ………………
ii) ………………
iii) ………………
iv) ……………....
4. Explain why stars that emit more energy than the sun have lower brightness on
Earth compared to of the sun
…………………………………………………………………………………
…………………………………………………………………………………
……………………………………………………….…………………………
5. Explain why you see lightening before you hear the thunder.
…………………………………………………………………………………
…………………………………………………………………………………
…………………………………………………………………………………
Illustrate:
1. Give three examples for electromagnetic waves.
i) …………………..
ii) …………………..
iii) ………………….
2. From the diagram below:
3.
a. Which color has the longest wavelength? ……………………………….
b. Which color has the shortest wavelength? ……………………………….
c. Which color has the highest frequency? ……………………………….
d. Which color has the lowest wavelength? ……………………………….
True or false
1.
2.
3.
4.
5.
6.
Visible light is the only type of electromagnetic eave that you can see.
The wavelengths of light waves are usually measured in nanometers.
Light travels in curved lines.
Electromagnetic waves need matter to travel.
Light waves travel faster than sound waves.
Matter usually interacts with light in only one way.
1) In each of the following pairs, circle the form of radiation with the LONGER
WAVELENGTH:
a. red light or blue light
b. microwaves or radiowaves
c. infrared radiation or red light
d. gamma rays or UV radiation
2) In each of the following pairs, circle the form of radiation with the GREATER
FREQUENCY:
a. yellow light or green light
b. x-rays or gamma rays
c. UV radiation or violet light
d. AM radio waves or FM radio waves
3) In each of the following pairs, circle the form of radiation with the LOWER
ENERGY:
a. red light or blue light
b. microwaves or radio waves
c. infrared radiation or red light
d. gamma rays or UV radiation
e. yellow light or green light
f. x-rays or gamma rays
g. UV radiation or violet light
h. AM radio waves or FM radio waves