Question

The speed of light in vacuum is $3\times {10}^{8}m/s.$ Sunlight takes about $8$ minutes to reach the Earth. Express distance of the Sun from Earth in standard form.

Answer 1

It is given that ,
Speed of light $=3\times {10}^{8}m/s$
Time taken by light to reach the Earth $=8minutes=8\times 60=480s$
We know that,
$Distance=speed\times time$
$=3\times {10}^8\times 480$
$=1440\times {10}^8$
$=1.440\times {10}^3\times {10}^8$
$=1.44\times {10}^{11}m$

Hence, the distance between the sun and the earth is $1.44\times {10}^{11}m$