Question

Define light year. Show the calculation for 1 Light year. [3 MARKS]

Answer 1

Definition: 1 Mark
Calculation: 2 Marks

1. Light year is the distance travelled by light in one year.

2. Speed of light = $3\times {10}^{8}m/s$
Time = 365 days,
S=d/t ; d=S×t
$d=3\times {10}^{8}m/s\times 365$days
$d=9.46\times {10}^{15}$ meters.