The number of complete wave cycles passing a fixed point per second, measured in hertz (Hz).
How many times something vibrates per second—high frequency means very rapid vibration.
Showing a random 20 of 102 problems.
Example 1
easy
A guitar string vibrates at G4=196 Hz. How long does one full vibration take?
Example 2
medium
A radio wave has frequency 500 kHz. Find its wavelength. Use c=3×108 m/s.
Example 3
challenge
A wave's frequency and wavelength are measured as 20 Hz and 1.5 m in medium A. In medium B, the wavelength is 2.4 m at the same frequency. Find the speeds in both media and their ratio.
Example 4
medium
What is the angular frequency ω of a wave with frequency 10 Hz?
Example 5
easy
Frequency has units of cycles per ___?
Example 6
challenge
A wave has frequency 50 Hz. In 0.5 s, how many complete wavelengths pass a point, and if each wavelength is 0.6 m, what distance does the wave travel?
Example 7
medium
A guitar string vibrates at a fundamental frequency of 330 Hz. What are the frequencies of the second and third harmonics? If the string length is 0.65 m, what is the wavelength of the fundamental?
Example 8
challenge
Two trains approach each other, each at 30 m/s. One sounds a horn at 500 Hz. What frequency does the listener on the other train hear? Use vsound=343 m/s.
Example 9
easy
Does higher frequency always mean a faster wave in a given medium?
Example 10
medium
A sonar pulse has frequency 25 kHz in water where sound travels at 1500 m/s. Find its wavelength.
Example 11
hard
A radar emits microwaves at 10 GHz. Find the wavelength in cm. Use c=3×108 m/s.
Example 12
easy
A speaker cone vibrates 440 times each second. State its frequency.
Example 13
medium
A clock's quartz crystal oscillates at 32,768 Hz. How long is one oscillation, in microseconds?
Example 14
hard
A string of length 0.5 m fixed at both ends has wave speed 200 m/s. Find the fundamental frequency.
Example 15
medium
Two waves move through the same string. Wave A has f=10 Hz, wave B has f=40 Hz. Which has the shorter wavelength?
Example 16
hard
Two tuning forks of frequencies 440 Hz and 444 Hz are sounded together. What is the beat frequency heard?
Example 17
medium
Two notes are produced: one at 200 Hz and one at 800 Hz. Which has the shorter period, and by what factor?
Example 18
easy
Convert 1 kHz to hertz.
Example 19
easy
A speaker vibrates 1000 times per second. What is its frequency?
Example 20
medium
A mass-spring system has k=250 N/m and m=0.4 kg. What is its oscillation frequency?