What distance does electromagnetic radiation travel in 7.50 msec?

Question

What distance does electromagnetic radiation travel in 7.50 msec?

I got 2250000m, but apparently, I'm wrong. Please help.

Answer 1

EM radiation travels at the speed of light, 3x10⁸ m/s (assuming a vacuum).

Using dimensional analysis, we can convert 7.50 msec to meters (m), if those are the desired units of distance.

7.50 msec x 1 sec / 1x10³ msec x 3x10⁸ m / sec = 2250000 m

Not sure why you say you're wrong as this is the answer I get as well.

Answer 2

Consider dimensional analysis:

1. Speed of light = 3.0 x 10^8 m/sec
2. 1 milli- = 0.001 = 1/1,000
3. Distance = speed x travel time

Plug in values and double check your answer. Make sure you have a step-by-step calculation that allows you to check your work. Be confident.