Wave Types
Comparing longitudinal and transverse disturbances
Sources of Sounds: What is the source of all sounds?
Video Instruction
showmethephysics.com
A Guitar String Through a Camera
The rolling-shutter effect makes the string appear to bend in unusual ways; it does not show the string’s actual shape at one instant.
Filming tips from the author: brightly backlight the strings, use a pencil as a support, and compare the front- and rear-facing cameras.
C. Vibrations & Waves
Transverse and Longitudinal Waves
Sound and a vibrating guitar string
Check Your Understanding
Which guitar is vibrating with the highest frequency?
The guitar on the right.
Check Your Understanding
5 quick questions — pick an answer to see if you’re right.
1. In a longitudinal wave, the particles of the medium vibrate
2. Which of these is an example of a longitudinal wave?
3. What is the source of all sounds?
4. A longitudinal wave is made of alternating regions called
5. When you hear a friend talk across the room, what happens to the air molecules near their mouth?
Slinky Waves
Students stretch a Slinky across the floor. In Trial 1, they push and pull one end back and forth along the Slinky’s length. In Trial 2, they shake one end side to side.
Which row correctly identifies the type of wave in each trial?
▶ Want a challenge? Open 6 more Regents-style questions (harder · mixed formats)
Challenge score: 0 / 6
C1. In Trial 1, what are the regions where the coils are bunched together called?
C2. A student makes the following claim.
Place a check mark in either the Support or Refute box. Justify your response.
C3. In Trial 1, the student moves the end back and forth 4.0 times per second, and the compressions are 0.50 m apart. Substitute numerical values into a mathematical representation that can be used to determine the speed of the wave. Then calculate the speed.
C4. A guitar string vibrates up and down, and the guitar body produces sound in the air. Which statement is correct?
C5. In Trial 1, the student now moves the end back and forth 8.0 times per second. The Slinky is stretched the same amount, so the wave speed stays 2.0 m/s. Determine the new distance between compressions.
C6. Students want to use the Slinky to model the two types of seismic waves produced by an earthquake. Describe which trial models a P-wave and which models an S-wave, and identify one way the Slinky model differs from real seismic waves.
