The Physics Lab
Waves that require a medium (like air or water) to travel.
What are mechanical waves?
A wave with a speed of 300 m/s and wavelength of 10m has this frequency.
What is 30 Hz?
When an ultrasonic wave hits an obstacle, one portion of the wave does this.
What is reflects (bounces back)?
A sound that is 20 decibels higher than another is this many times more intense.
What is 100 times?
This type of wave doesn't move the medium forward, it just vibrates it.
What is a mechanical wave?
In a longitudinal wave, the medium moves in this direction relative to the wave.
What is parallel?
The formula used to calculate wave speed.
What is Velocity = Wavelength times Frequency?
When a wave hits a boundary, the portion that doesn't reflect does this.
What is transmits (passes through/is absorbed)?
If a conversation is 40 dB and a whisper is 20 dB, the conversation is this many times more intense.
What is 100 times?
Sound cannot travel through this "nothingness" found in outer space.
What is a vacuum?
This term describes the "height" of a wave from its midpoint.
What is amplitude?
Find the frequency of a wave traveling 320 m/s with a 12m wavelength.
What is 26.67 Hz?
These high-frequency waves are used by sensors to detect obstacles.
What are ultrasonic waves?
Increasing this feature of a sound wave makes it sound louder to the human ear.
What is amplitude?
Sound travels through these types of waves.
What are longitudinal waves?
This specific part of a longitudinal wave is where the particles are furthest apart.
What is a rarefaction?
Every 10-decibel increase represents a 10-fold increase in this.
What is intensity?
This is what we call the "frequency" of a sound as perceived by our ears.
What is pitch?
High-pitch sounds are characterized by having these two wave features.
What are high frequency and short wavelength?
This is the speed of a jet flying at "Mach 1."
What is the speed of sound?
This happens to the wavelength of a sound as its frequency increases (if speed is constant).
What is it decreases (gets shorter)?
Calculating the frequency of a wave with a speed of V and a wavelength of L.
What is V/L?
This part of an ultrasonic sensor's signal returns to the device to provide data.
What is the reflected portion (the echo)?
These "gentle" waves move a pool float up and down but not toward the shore.
What are surface waves?
Light is different from sound because it does not require one of these.
What is a medium?