Physics

# It takes time 8 min for light to reach from the sun to the earth surface. If speed of light is taken to be $3 \times 10^{8} ms^{-1}$, find the distance from the sun to the earth in km.

##### SOLUTION
Given:
Time = 8 min
Speed = $3 \times 10^{8} ms^{-1}$

Time is not given in the standard from, i.e., in seconds.
So first convert to seconds;
$1 min$ = $60s$
$8 min$ = $8$ $\times$ $60s = 480s$
Distance  $=s$ $\times$ $t$
=  $3 \times 10^{8} \times 480$
$= 1.44 \times 10^{8} km$

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Subjective Medium Published on 18th 08, 2020
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