The speed of light is 300 000 km/s. Light takes 8 1/2 minutes to travel from the sun to the earth. How far is the sun to the earth In kilometres. Express this in standard index form

Question

Standard form

Answer 1

8½ minutes=480+30=510 seconds.

Therefore since distance=speed×time,

distance from earth to sun=300000×510=153 million km.

This can be written 1.53×10⁸km.