Answer:
B
Explanation:
Electromagnetic spectrum includes visible light which we see all the time reflecting off objects to give them colours, mechanical waves like sound require something to move in, its the reason why people say you can't scream in space because space is a giant vacuum. No not the kind you use to clean up the mess you made from breakfast. The kind that has no air. So sound can be heard on earth as it is not a vacuum, air moves freely and transfers sounds vibrations all around you to be absorbed by walls and other stuff in comes in contact with.
Extra information:
Sound travels further in water because the molecules are closer together meaning that transferring the energy is easier. This is how Blue wales can communicate from hundreds of miles away.
Hello, I see you are in a jam. Lemme help.
1.) True
2.) True
3.) True
4.) True
5.) True
LOL these are all true ;)
The power of the lens is 2 diopter means that this lens has a focal length of 1/2 meter.
The focal length = 1 ÷ ( the number of diopters)
If one's glass prescription shows that the power of the lens is 2 diopter it means that the person is far-sighted. It means if a person needs to see something which is quite distant then his eyes need extra lens power to focus on it. Moreover, if there's a sign convention it means '+' indicates a convex lens and '-' concave lens. Also in-camera close up lens are also measured in terms of diopter.
I hope this answer helps.
To learn more about lenses,
brainly.com/question/766997
brainly.com/question/17014859
Try B if it is not it I am sorry I checked on Google
Hello Again! I think the Answer might be 220 m! ( 1/2) ( 21 m/s + 0 m/s) (21 s) = 220 m
