## Page T - Doppler Effect

The sound you hear as a vehicle is approaching you and then passing you changes in pitch – and just like everything in Physics, the change in pitch can be measured and explained mathematically.

Page Sb-T includes a series of questions to guide the student through the steps involved in calculating the Doppler Effect. However, it can be quite intimidating for some students. Here’s my recommendation for tackling the subject:

**For students who excel with math or are “math-inclined”:**

Do your best to follow the example in the PACE and see how each step was calculated. Then complete pages Sb-T to the best of your ability. Correct any errors so that you understand how to calculate the Doppler Effect. On the Checkup, do questions 35-42.

**For students with average math ability:**

- Study the example in the PACE to see how each step was calculated
- Work through the steps on pages Sb-T, but have the scorekey nearby and check your work after each step.
- If you feel you are “getting it” then do questions 35-42 on the check-up
- If you really don’t understand all the steps and math involved, ask your supervisor if you may skip questions 35-42 on the check-up (tell her “Mr. Anger said you could!”)

**For students who really struggle with algebra (only with your supervisor’s permission):**

- Read the example in the PACE
- Copy the steps from the scorekey into your PACE for pages Sb-T
- Skip questions 35-42 on the check-up
- NOTE: For the Self Test and PACE test you need to know what the Doppler Effect is (definition) but will not be required to do all the math steps.

## Page Q - "Echo" problems

The main problem students have solving these problems involving echoes is recognizing when the distance being given or asked for is the total distance the echo travels, OR the distance from one point to the other side. An echo travels both directions – which is twice the distance from one side to the other. Read the question carefully and underline what is being asked for!

Also remember that you can use the “Magic Triangle” to solve distance-rate-time problems: put Distance in the top, and Rate and Time in the bottom.