posted by KD on .
Few question about astronomy:
1.how many centimetres is equivalent to a light-nanosecond
2. How long is an astronomical unit (AU) in light-minutes (1min, i.e., the distance that light travels in a vacuum in one minute)?
Please show the calculation if there is any
1. speedlight*time= distance
3E8m/s*1E2cm/m*1E-9sec=3E1 or 30 cm
2. Sunlight reaches Earth in 8.3 minutes. The Earth-Sun distance is therefore 8.3 light-minutes.
One way to get the answer is to divide the Earth-Sun distance by the distance travelled by light in one minute, using the same units.