The speed of light is about 300,000 km/s (3 × 105 km/s). How far does light travel in 30 seconds?
A)900 thousand km (900,000, or 9 × 105 km)
B)9 million km (9,000,000, or 9 × 106 km)
C)10 thousand km (10,000, or 106 km)
D)300 thousand km (300,000, or 3 × 105 km)

Question

Quizplus · Accepted Answer

To find out how far light travels in 30 seconds, we need to multiply the speed of light by the time it travels. 
Distance = Speed × Time 
Therefore, Distance = 300,000 km/s × 30 s = 9,000,000 km (9 × 106 km). The best choice is B, 9 million km.

The Speed of Light Is About 300,000 Km/s (3 ×