# Homework Help: Physical Science question

1. Feb 15, 2012

### cwalker8184

How many meters will light travel in 83.8 hours?

what I came up with is

(3x10 m/s) (83.8hr) = 2.5 14 x 10

2.5 14x10 m

teacher marked it wrong very confused.

2. Feb 15, 2012

### PeterO

I hope you really meant 3x108 m/s for the speed of light.

Ponder this:

If you travel at 30 miles per hour for 10 minutes will you end up 300 miles away?

If you walk at 2 m/s for 8 hours will you be just 16m away.

Hopefully you see the problem in those two, and should thus get the problem with your answer.

3. Feb 15, 2012

### cwalker8184

No, that was the exact question. I took a Physical Science test and I got it wrong.

1. How many meters will light travel in 83.8 hours?

I totally did not understand the question.

4. Feb 15, 2012

### PeterO

well it travels 3x108 metres in one second
so
60 times 3x108 metres in one minute
so
60 times 60 times 3x108 metres in one hour
so
83.8 times 60 times 60 times 3x108 metres in 83.8 hours

Did you understand that driving at 30 miles an hour for 10 minutes won't get you 300 miles away?
Did you understand that walking at 2 m/s for 8 hours will get you more than 16 m away?

Do you know how far that driving would get you, and how far you would walk?