**AP Physics 1 Question 302: Answer and Explanation**

### Test Information

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**Question: 302**

**10.** The picture above shows a tube open at one end. A standing wave is represented by the dotted curves. If this wave has frequency *f*, what is the frequency of the next harmonic that can be formed in this tube?

- A.
- B. 2
*f* - C. 3
*f* - D. The above wave shows the highest possible harmonic frequency for this system.

**Correct Answer:** C

**Explanation:**

**C**

Remember that in a system with one closed end and one open end, there will be a node at one end and an antinode at the other. From the drawing, you can see that the tube is the length of 1/4 wavelength of this standing wave. That means that this wave is the fundamental standing wave, also called the first harmonic. As you'll learn on this page, the next harmonic is the third harmonic, and it has 3 times the frequency of the first harmonic.