43.
Why
is
the
distance
between
stars
expressed
in
light
years?
What
do
you
understand
by
the
statement
that
a
star
is
eight
light
years
away
from
the
Earth?
Answers
Answer:
Many astronomical objects like stars or galaxies are very far away from the earth & giving their distances in the kilometres unit becomes very inconvenient.
Light-year is a large unit and equals the distance travelled by light in one year. Hence, the large distances are expressed in light-years.
1 light-year = 9.46 x 1012 km
If a star is located 8 light-years away from the earth, it means that the distance between the star and the earth is the distance light would travel in eight years.
So, the distance between the earth and star = 8 ✕ (9.46 ✕ 1012) = 7.6 ✕ 1013 km.
hope it will helps you
please mark me as brainlest
Answer:
1) because the time taken by light to reach is in a year means light reaches there in a year
2) it would take 8 years to reach there traveling at the speed of light in vaccume
which is 3×10 the power 8