2. Where the equation comes from If you know how far you’ve gone and how long it took you to get there its pretty easy to figure out how fast you were going using this equation: Speed = distance/time s = d/t Except in physics we use the word velocity so it becomes: v = d/t

3. Where the equation comes from Velocity = distance/time v = d/t For waves we can do something similar. We can watch a wave go by. One whole wave from crest to crest and measure its length. What do we call that? Oh right… wavelength (λ) And let’s time how long it takes for that one wave to go by. We have a name for that too. The time it takes for ONE wave to go by is the period (T).

4. Where the equation comes from Velocity = distance/time v = d/t So for waves the equation becomes: v = λ/T And remember f = 1/T and frequency is usually easier to measure so that equation becomes: v = λ f

5. Wavespeed So this equation is referred to as the wavespeed equation. v = λ f If you know the wavelength and the frequency you can calculate the wavespeed really fast (no pun intended). One thing worth noting: changing the wavelength OR the frequency does NOT change the speed. Increasing the wavelength makes the frequency go down and vice versa. Wavelength and frequency have an inverse relationship, but neither can change the wavespeed.

6. Wave Stats Sound travels at about a speed of 340 m/s Which is about 760 mph if you were wondering! And 0.2 miles per second. So sound can travel one mile in about 5 seconds. Which is NOTHING compared to light. All light and electromagnetic waves travel at a speed of 300,000,000 m/s or 3 x 10 8 m/s Which is about 186,300 miles per SECOND! Which is from San Francisco to New York and back again 38 times in ONE SECOND.