AP Physics 2 Quiz: Periodic Waves

What this quiz covers

This quiz focuses on Periodic Waves, giving you a quick way to practice the rules, question types, and explanations that matter most for AP Physics 2.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

Question 1

1. $v=\dfrac{T}{\lambda}$ because speed is time per distance.
2. $v=\lambda T$ because distance and time multiply.
3. $v=\dfrac{\lambda}{T}$ because one wavelength passes in one period. (correct answer)
4. $v=\dfrac{1}{\lambda T}$ because speed is inverse of wave size.

Question 2

1. $\lambda_2=2\lambda_1$ because higher frequency means longer wavelength.
2. $\lambda_2=\lambda_1$ because the string sets wavelength directly.
3. $\lambda_2=\dfrac{1}{2}\lambda_1$ because the wave speed is the same. (correct answer)
4. $\lambda_2=\dfrac{1}{2}\lambda_1$ because the amplitude is larger.

Question 3

1. The wavelength becomes $\tfrac{1}{2}\lambda$ because speed stays constant. (correct answer)
2. The wavelength stays $\lambda$ because amplitude determines wavelength.
3. The wavelength becomes $2\lambda$ because speed increases with frequency.
4. The wavelength becomes $\tfrac{1}{4}\lambda$ because both speed and frequency double.

Question 4

1. $\lambda' = \tfrac{1}{2}\lambda$ because halving $T$ doubles $f$ at constant speed (correct answer)
2. $\lambda' = 2\lambda$ because halving $T$ halves the frequency
3. $\lambda' = \lambda$ because the rope properties determine wavelength directly
4. $\lambda' = 4\lambda$ because the wave speed increases as $T$ decreases

Question 5

1. It becomes $0.40\ \text{m}$ because doubling frequency halves wavelength at constant speed (correct answer)
2. It becomes $0.20\ \text{m}$ because doubling frequency quarters wavelength
3. It becomes $1.6\ \text{m}$ because frequency and wavelength increase together
4. It becomes $0.80\ \text{m}$ because wave speed fixes wavelength

Question 6

1. $\lambda=0.40\ \text{m}$ because $\lambda=\dfrac{v}{f}$. (correct answer)
2. $\lambda=0.10\ \text{m}$ because $\lambda=\dfrac{1}{vf}$.
3. $\lambda=10\ \text{m}$ because $\lambda=vf$.
4. $\lambda=2.5\ \text{m}$ because $\lambda=\dfrac{f}{v}$.

Question 7

1. The wavelength stays $\lambda$ because period does not affect wavelength.
2. The wavelength becomes $9\lambda$ because both period and speed triple.
3. The wavelength becomes $\tfrac{1}{3}\lambda$ because frequency increases.
4. The wavelength becomes $3\lambda$ because the wave speed stays constant. (correct answer)

Question 8

1. The frequency becomes $4f$ because both speed and frequency must increase together.
2. The frequency becomes $2f$ because wave speed stays constant. (correct answer)
3. The frequency becomes $\tfrac{1}{2}f$ because shorter wavelength means lower frequency.
4. The frequency stays $f$ because amplitude determines frequency.

Question 9

1. The period becomes $\tfrac{1}{9}T$ because speed and frequency both triple.
2. The period becomes $3T$ because period increases with frequency.
3. The period becomes $\tfrac{1}{3}T$ because period is the inverse of frequency. (correct answer)
4. The period stays $T$ because wave speed is unchanged.

Question 10

1. The wavelength becomes $\tfrac{3}{2}\lambda$ because the frequency stays the same. (correct answer)
2. The wavelength becomes $\tfrac{2}{3}\lambda$ because higher speed means higher frequency.
3. The wavelength becomes $\tfrac{9}{4}\lambda$ because both speed and period increase.
4. The wavelength stays $\lambda$ because the medium does not affect wavelength.

Question 11

1. $T' = 3T$ because period increases with frequency
2. $T' = \tfrac{1}{3}T$ because $T=\tfrac{1}{f}$ (correct answer)
3. $T' = T$ because wave speed stays constant
4. $T' = \tfrac{1}{9}T$ because wavelength decreases by a factor of 3

Question 12

1. $\lambda' = 4\lambda$ because speed increases as frequency decreases
2. $\lambda' = 2\lambda$ because wave speed stays constant (correct answer)
3. $\lambda' = \lambda$ because amplitude sets the spacing of crests
4. $\lambda' = \tfrac{1}{2}\lambda$ because wavelength is proportional to frequency

Question 13

1. $\lambda' = \tfrac{1}{4}\lambda$ because the speed doubles with frequency
2. $\lambda' = 2\lambda$ because higher frequency means longer spacing
3. $\lambda' = \tfrac{1}{2}\lambda$ because $v=f\lambda$ and $v$ is constant (correct answer)
4. $\lambda' = \lambda$ because wavelength depends only on loudness

Question 14

1. $T' = 2T$ because angular frequency is inversely related to wavelength
2. $T' = \tfrac{1}{4}T$ because doubling $\omega$ quadruples $f$
3. $T' = T$ because amplitude $A$ is unchanged
4. $T' = \tfrac{1}{2}T$ because $\omega = \tfrac{2\pi}{T}$ (correct answer)

Question 15

1. $\lambda' = 4\lambda$ because doubling $f$ doubles $c$
2. $\lambda' = 2\lambda$ because wavelength increases with frequency
3. $\lambda' = \lambda$ because speed changes with amplitude
4. $\lambda' = \tfrac{1}{2}\lambda$ because $c=f\lambda$ remains constant (correct answer)

Question 16

1. $\lambda' = \lambda$ because frequency determines wavelength regardless of speed
2. $\lambda' = 2\lambda$ because $\lambda=\tfrac{v}{f}$ and $f$ is unchanged (correct answer)
3. $\lambda' = \tfrac{1}{2}\lambda$ because wavelength decreases when speed increases
4. $\lambda' = 4\lambda$ because doubling speed doubles frequency and wavelength

Question 17

1. The wavelength stays $\lambda$ because amplitude sets the wavelength.
2. The wavelength becomes $\tfrac{1}{2}\lambda$ because wavelength follows frequency directly.
3. The wavelength becomes $2\lambda$ because the wave speed stays constant. (correct answer)
4. The wavelength becomes $4\lambda$ because the speed doubles when frequency halves.

Question 18

1. The period becomes $\tfrac{1}{4}T$ because longer wavelength means higher frequency.
2. The period stays $T$ because wavelength does not affect period.
3. The period becomes $4T$ because the wave speed stays constant. (correct answer)
4. The period becomes $16T$ because both wavelength and speed increase by 4.

Question 19

1. The frequency becomes $\tfrac{1}{2}f$ because frequency is proportional to period.
2. The frequency becomes $2f$ because frequency is the inverse of period. (correct answer)
3. The frequency stays $f$ because wave speed is unchanged.
4. The frequency becomes $4f$ because halving period doubles speed and frequency.

Question 20

1. The wavelength stays $\lambda$ because speed and frequency are unchanged. (correct answer)
2. The wavelength halves because larger amplitude increases frequency.
3. The wavelength doubles because amplitude determines wavelength.
4. The wavelength increases because wave speed increases with amplitude.