Is light year a fundamental unit or derived unit?

Answer 1

Distance. One light-year is the distance that light travels in one year.

Light travels at 186,000 miles per second, or 300,000 kilometers per second. This speed is sometimes abbreviated as "c".

Answer 2

A light year is a unit of astronomical distance, defined as the distance that light travels in one year in a vacuum. It is a derived unit because it is derived from the speed of light and the time period of one year.

Answer 3

a light year refers to the distance it takes light to travel in one year, in practice, if you were one light year from the earth, and had a telescope powerful enough to veiw activities on the surface, you would be seeing activity's one year in the past from the moment you are viewing them, becasue the light waves you are looking at would have taken a year to get to where you are viewing them from... If you are asking: What do astronomers mean when they say that powerful telescopes look back into the past, that is because of the speed of light and 'light years'.

Although very fast indeed, light does not move instantly as it seems; it takes time to reach us from very, very distant objects such as stars. A light year is how far light will travel in a year = 9,400,000,000,000km. Stars are much much farther away than that, so what we see of them is actually how they looked years ago, but the light has only just got here.

Seeing something, anything, is literally receiving light from it to your eyes - either reflected off it (the Moon, that coffee mug, your sister's face) or produced by it if it is a light source (a star, your PC screen, a light bulb).

So, if a star trillions of kilometres away blew up yesterday, we will not see the explosion (called a super nova) for many years yet. All this means that as we develop better, more powerful telescopes, we can see right back towards the beginning of the universe and the largest explosion of all: the Big Bang. Just don't ask what there was before that, because the answer is nothing, no light, not even time!

Answer 4

No. A light-year is a measure of distance; the distance that light travels in one year.

Light travels at approximately 186,000 miles per second, or 300,000 kilometers per second. There are 60 seconds in a minute, 60 minutes in an hour, 24 hours in a day, and 365.24 days per year. Multiply all those numbers together, and that's how far a "light-year" is.

The nearest star to our Sun is Proxima Centauri, at about 4.2 light-years. For comparison, the distance between the Earth and the Sun is 500 light-SECONDS.

Answer 5

A light year is a measure of distance. It is the distance that light travels in one year. 1 light year = 9,460,528,400,000 kilometers = 5,878,499,810,000 miles

Answer 6

"Light-year" is a unit of distance. It's the distance that light travels

through vacuum in one year. Roughly 5,878,700,000,000 miles.

Answer 7

It measures distance. It goes by the distance light can travel in one year. It is about 10 trillion kilometers.

Answer 8

NO, light years measure distance more specifically the distance light travels in a year

Answer 9

No, a light year is a measure of distance.

Answer 10

Fundamental unit all examples