11. Answer the following questions based on stars and light years: a) A star is 10 light years away from Earth. Suppose it dies on a certain day after an explosion, after how much time will we see the explosion from Earth? Give reasons for your answer. b) A star is 12 light minutes from a planet. If the speed of light is 3,00,000 km/s, what is the distance of the star from the planet in km?
Answers
Explanation:
Answer:
Answer:1)-Light year is one of the basic units of measurement of distance between celestial bodies in the universe others are astronomical unit(AU) ,parsec and so on.light travels at a staggering speed of 3*10^8 metre per second,to put that into perspective in one second light can travel around the Earth 8 times .So light year is the distance travelled by light in one year .An year has 365*24*60*60 =31,536,000 seconds .This when multiplied with the speed of light gives 9,460,730,472,581 kilometres.There is nothing in the universe that travels faster than light.Even with this incredible speed light from our sun takes 8 mins to reach us ,Thus we are seeing the sun as it was 8 minutes ago.The nearest star proxima centauri is about 4 light years away so we at this very moment are seeing it as it was 4 years ago. So if a star which is 100 light years away from the earth explodes this very moment we would see the explosion exactly 1oo years from now provided we live that long which won't be true in most cases. We will be long dead before the light reaches us.our children might be fortunate to witness this event.
Answer:
Good question,
Light year is a unit of astronomical distance equivalent to the distance that light travels in one year, which is 9.4607 × 10^12
km (nearly 6 million million miles).
So it takes 10 years to see it !!
Hope that doubt is clarified …
(I saw a good future in you…keep learning all the best