The Period, or the time it takes for wave to complete on wavelength, is related to ____________Frequency
A wave has a frequency of 40 hertz. What is the period of the wave?
• Know:• Find:• Formula:•
Answer:
f = 40hertzPeriod
T = 1/ f
T = 1/f = 1/40 = 0.025s
A wave has a period of 2 seconds. What is the frequency of the wave?
• Know:• Find:• Formula:•
Answer:
T = 2sfrequency
f = 1/ T
f= 1/T = 1/2 = 0.5Hz
The only thing that affect wave speed is the medium
We can use two properties of a wave to calculate the speed:
Frequency- (how many waves per second)Wave Length- (distance between waves)
Finding Speed of a Wave
The wavelength for a wave is 0.5 meter, and its frequency is 40 hertz. What is the speed of the wave?
• Know:• Find:• Formula:•
Answer:
f = 40hertz ƛ = 0.5mSpeed
v = fƛ
v = 40hrtz x 0.5m = 20m/s
The period of a wave is 10 seconds and the wavelength is 2 meters. What is the wave speed?
• Know:• Find:• Formula:•
Answer:
T = 10s ƛ = 2mWave Speed
v = f ƛ
v = f ƛ =
f = 1/T = 1/10 = 0.1hz
v = 0.1hrtz x 2m = 0.2m/s
Can rearrange formula to solve for either frequency or wavelength
A sound wave has a speed of 400m/sec and a frequency of 200Hz. What is its wavelength?
• Know:• Find:• Formula:•
Answer:
v = 400m/s f= 200HzWavelength
v =fƛ
v/f = fƛ / f
ƛ = v/f = 400/200 =2m
Summarizer: Try these on your own!
Johnny is making waves on a slinky. It takes 0.5s for one complete wavelength. The wavelength of the waves is 2m. What is the speed of the waves John-boy made?
• Johnny now creates waves with a speed of 3m/s, with a wavelength of 0.25m.
What is the frequency of the waves?
What is the period of the waves?