Speed of light; distance from earth to sun

AI Thread Summary
The average distance from Earth to the sun is approximately 93 million miles, and light travels at a speed of 300 million meters per second. To determine how long it would take for the effect of the sun being extinguished to be visible on Earth, one must use the formula for speed, which is distance divided by time. The discussion suggests converting miles to meters or the speed of light from meters per second to miles per second to facilitate calculations. Following this approach will lead to the correct answer regarding the time delay in visibility.
lonelyassassin
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Ok, I got this problem and I don't know where to start...

"The average distance from the Earth to the sun is 9.30 x 10^7 miles. Light travels at a speed of 3.00 x 10^8 meters per second. If the sun were to be suddenly extinguished, how many minutes would it take for the effect to be visible here on earth? Show work."

Can someone tell me how do I start?
 
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Hi there lonelyassassin and welcome to PF,

HINT:

Speed = \frac{Distance}{Time}
 
Ok, from your hint, I got:
http://img339.imageshack.us/img339/8793/work1bu5.jpg

First of all, am I on the right track?
If I am, then the next step should be to factor label to get to minutes, but the meter/second is on both the denominator and numerator. And the miles is already on the numerator.

Can you tell me how to proceed now?
 
Last edited by a moderator:
Convert miles to meters or convert meters/second into miles/second and you'll have your answer.
 
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