Question

1. what term describes the number of waves per second? (choose one)

a)wavelength
b)frequency
c)period
d)speed

1. what is the period of a pendulum with a string length of 2m?

1. the term \pitch\ in music, refers to the ____________ of a wave?

a)strength
b)velocity
c)amplitude
d) frequency

1. list the primary and secondary colors of light under the correct headings:

primary	secondary

1. what is the correct unit for velocity

a) m/s
b) hz
c) m
d) s

Explanation:

Question 17

To determine the term for waves per second, recall wave definitions:

• Wavelength: distance between waves.
• Frequency: number of waves per second (unit: Hz).
• Period: time for one wave.
• Speed: distance per time (e.g., m/s).

Thus, frequency matches "waves per second."

Step1: Recall Pendulum Period Formula

The period \( T \) of a simple pendulum is given by \( T = 2\pi\sqrt{\frac{L}{g}} \), where \( L = 2\,\text{m} \) (length) and \( g = 9.8\,\text{m/s}^2 \) (gravity).

Step2: Substitute Values

Plug \( L = 2 \) and \( g = 9.8 \) into the formula:
\( T = 2\pi\sqrt{\frac{2}{9.8}} \approx 2\pi\sqrt{0.204} \approx 2\pi(0.452) \approx 2.84\,\text{seconds} \).

In music, "pitch" relates to how high/low a sound is. Wave properties:

• Strength: Not a standard wave term.
• Velocity: Speed of wave (not pitch).
• Amplitude: Wave height (relates to loudness).
• Frequency: Number of waves per second (higher frequency = higher pitch).

Thus, pitch corresponds to frequency.

Answer:

b) frequency

Question 18