PROBLEM 30P

How far does light travel in each time period?

(a) 1.0 s

(b) 1.0 day

(c) 1.0 yr

Solution 30P

a)1.0s

1.798791×1010m/min=1.798791×107 km/min=1.117886×107mi/min, nearly.

Explanation:

The speed of light in a vacuum in meters per second is

c=299,798,458 m/s

b)1 day

There's 24 hours in a standard day. Each hour has 3600 seconds in it (60 minutes, each of 60 seconds, 60 * 60 = 3600).

So, that means light travels 3600 * 24 * 300 000 km in one 24-hour day, or about 25920000000 km. That's really tedious to write out (imagine a light year!), so one can either use AU (astronomical units), or just use the distance measure "1 light day".

c)1 year

Light travels at "the speed of light" which has been measured to be about 300,000 km/s (kilometers per second) or 186,000 m/s (miles per second) in empty space. Doing the math, a Light-year is 9.46 trillion km, or 5.88 trillion miles. Trillion is 10^12.