<< Chapter < Page Chapter >> Page >

A transverse wave is traveling left to right. Which of the following is correct about the motion of particles in the wave?

  1. The particles move up and down when the wave travels in a vacuum.
  2. The particles move left and right when the wave travels in a medium.
  3. The particles move up and down when the wave travels in a medium.
  4. The particles move right and left when the wave travels in a vacuum.
Got questions? Get instant answers now!
The image shows a graph of an oscillating line. The y-axis has displacement from negative 1 meter to positive 1 meter. The x-axis has time from 0 seconds to 8 pi seconds. The line starts at 0, positive 1, curves down to pass through displacement 0, and meets pi, negative one. The line curves up and passes through displacement equals 0 again, and then meets 2 pi, positive 1. It continues this way, finally meeting 8 pi, positive 1.

The graph shows propagation of a mechanical wave. What is the wavelength of this wave?

2 π m

Got questions? Get instant answers now!

Section summary

  • A wave is a disturbance that moves from the point of creation with a wave velocity v w size 12{v rSub { size 8{w} } } {} .
  • A wave has a wavelength λ size 12{λ} {} , which is the distance between adjacent identical parts of the wave.
  • Wave velocity and wavelength are related to the wave’s frequency and period by v w = λ T size 12{v size 8{w}= { {λ} over {T} } } {} or v w = . size 12{v size 8{w}=fλ} {}
  • A transverse wave has a disturbance perpendicular to its direction of propagation, whereas a longitudinal wave has a disturbance parallel to its direction of propagation.

Conceptual questions

Give one example of a transverse wave and another of a longitudinal wave, being careful to note the relative directions of the disturbance and wave propagation in each.

Got questions? Get instant answers now!

What is the difference between propagation speed and the frequency of a wave? Does one or both affect wavelength? If so, how?

Got questions? Get instant answers now!

Problems&Exercises

Storms in the South Pacific can create waves that travel all the way to the California coast, which are 12,000 km away. How long does it take them if they travel at 15.0 m/s?

t = 9 . 26 d size 12{d= {underline {9 "." "26 d"}} } {}

Got questions? Get instant answers now!

Waves on a swimming pool propagate at 0.750 m/s. You splash the water at one end of the pool and observe the wave go to the opposite end, reflect, and return in 30.0 s. How far away is the other end of the pool?

Got questions? Get instant answers now!

Wind gusts create ripples on the ocean that have a wavelength of 5.00 cm and propagate at 2.00 m/s. What is their frequency?

f = 40 . 0 Hz size 12{v rSub { size 8{w} } = {underline {"40" "." "0 Hz"}} } {}

Got questions? Get instant answers now!

How many times a minute does a boat bob up and down on ocean waves that have a wavelength of 40.0 m and a propagation speed of 5.00 m/s?

Got questions? Get instant answers now!

Scouts at a camp shake the rope bridge they have just crossed and observe the wave crests to be 8.00 m apart. If they shake it the bridge twice per second, what is the propagation speed of the waves?

v w = 16 . 0 m/s size 12{v rSub { size 8{w} } = {underline {"16" "." "0 m/s"}} } {}

Got questions? Get instant answers now!

What is the wavelength of the waves you create in a swimming pool if you splash your hand at a rate of 2.00 Hz and the waves propagate at 0.800 m/s?

Got questions? Get instant answers now!

What is the wavelength of an earthquake that shakes you with a frequency of 10.0 Hz and gets to another city 84.0 km away in 12.0 s?

λ = 700 m size 12{λ="700"`m} {}

Got questions? Get instant answers now!

Radio waves transmitted through space at 3 . 00 × 10 8 m/s size 12{3 "." "00" times "10" rSup { size 8{8} } "m/s"} {} by the Voyager spacecraft have a wavelength of 0.120 m. What is their frequency?

Got questions? Get instant answers now!

Your ear is capable of differentiating sounds that arrive at the ear just 1.00 ms apart. What is the minimum distance between two speakers that produce sounds that arrive at noticeably different times on a day when the speed of sound is 340 m/s?

d = 34 . 0 cm size 12{d= {underline {"34" "." "0 cm"}} } {}

Got questions? Get instant answers now!

(a) Seismographs measure the arrival times of earthquakes with a precision of 0.100 s. To get the distance to the epicenter of the quake, they compare the arrival times of S- and P-waves, which travel at different speeds. [link] ) If S- and P-waves travel at 4.00 and 7.20 km/s, respectively, in the region considered, how precisely can the distance to the source of the earthquake be determined? (b) Seismic waves from underground detonations of nuclear bombs can be used to locate the test site and detect violations of test bans. Discuss whether your answer to (a) implies a serious limit to such detection. (Note also that the uncertainty is greater if there is an uncertainty in the propagation speeds of the S- and P-waves.)

The figure shows a seismograph put on a wooden table. Its top is labeled as “Hands off glass, please”. Below it there are some buttons are shown and a paper roller is fitted in the seismograph to print the observation by the machine. On the right and left of the roller, two vertical cable slots are given.
A seismograph as described in above problem.(credit: Oleg Alexandrov)
Got questions? Get instant answers now!
Practice Key Terms 4

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, College physics for ap® courses. OpenStax CNX. Nov 04, 2016 Download for free at https://legacy.cnx.org/content/col11844/1.14
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'College physics for ap® courses' conversation and receive update notifications?

Ask