I need someone to go over my answers please, I was haveing trouble on these three. If I got it wrong will you tell me how I should solve it with formulas please.
What is the wave speed for a wave of 5 meters wavelength that has a frequency A) 25.6 m/s.
B) 64 m/s.
C) 128 m/s.
D) 640 m/s.
I think its a
A string on a guitar is 0.4 m long and produces 360 Hz as its fundamental tone. If you press on the string so that you reduce its free length to 0.2 m, what tone will it produce?
A) 270 Hz.
B) 480 Hz.
C) 540 Hz.
D) 720 Hz.
I think it is D
You have a tuning fork that produces a frequency of 512 Hz in air. You submerge it in the swimming pool and strike it against the wall underwater. The speed of sound in water is 1500 m/s. What will the resulting frequency and wavelength be?
A) 740 Hz, 3.41 m
B) 740 Hz, 0.773 m
C) 512 Hz, 3.41 m
D) 512 Hz, 2.93 m
In the first question, you did not provide the frequency.
Your answer to the second question is correct.
In the third question, the frequency remains the same under water and (1500 m/s)/(frequency) is the new wavelength.
i think the first question the answer is A. wavespeed=frequency x wavelength
freq=128hz
wavelength=5 meters
so multiplied equals 640
To find the wave speed (v) for a wave of 5 meters wavelength, we can use the formula:
v = λ * f
where λ represents the wavelength and f represents the frequency.
For the first question, we are given a wavelength of 5 meters and we need to find the wave speed for different frequencies. Let's calculate using the given options:
A) v = 5 meters * 25.6 Hz = 128 m/s
B) v = 5 meters * 64 Hz = 320 m/s
C) v = 5 meters * 128 Hz = 640 m/s
D) v = 5 meters * 640 Hz = 3200 m/s
Since none of the options match your initial choice of A, let's go through the calculations to determine the correct answer.
The formula we used is v = λ * f. Rearranging the formula gives us:
f = v / λ
Plugging in the values for option A:
f = 25.6 m/s / 5 meters = 5.12 Hz
Therefore, the correct answer is A) 5.12 Hz.
For the second question, we need to find the new tone produced when the length of the string is reduced to 0.2 m.
To solve this, we can use the formula:
f1 / f2 = L1 / L2
where f1 and f2 represent the frequencies and L1 and L2 represent the lengths. We are given the initial frequency f1 as 360 Hz and the initial length L1 as 0.4 m. We need to find f2 when the length is changed to 0.2 m.
Plugging in the values:
360 Hz / f2 = 0.4 m / 0.2 m
Simplifying the equation:
360 Hz / f2 = 2
Cross multiplying:
f2 = 360 Hz / 2
f2 = 180 Hz
Therefore, the correct answer is A) 180 Hz.
For the third question, we are given a tuning fork that produces a frequency of 512 Hz in air and asked to find the resulting frequency and wavelength when it is submerged in water.
To solve this, let's use the formula:
v = λ * f
In this case, the wave speed (v) is the speed of sound in water, which is given as 1500 m/s, and we need to find the resulting frequency and wavelength.
Using the formula:
1500 m/s = λ * 512 Hz
Rearranging the equation to solve for the wavelength (λ):
λ = 1500 m/s / 512 Hz ≈ 2.93 m
So, the wavelength in water is approximately 2.93 m.
Now, to find the resulting frequency (f) in water, we can use the equation:
f = v / λ
Plugging in the values:
f = 1500 m/s / 2.93 m ≈ 512 Hz
Therefore, the correct answer is D) 512 Hz, 2.93 m.