Standing Wave Equation help?

Question

How do I solve this?
A wave has an amplitude of .0800 m and is moving 7.33 m/s. One oscillator in the wave takes .115 s to go from the lowest point in it's motion to the highest point. Find the wavelength of the wave.

 

I tried solving this by using f=v/λ and finding λ and then multiplying that by .115 and I got 91.6 but that's not the right answer and I'm not sure where I messed up

Answer 1

I'm not sure, but I think of a wave length from a minimum value to the next minimum value, where it starts to repeat...or a maximum to the next maximum.

 

Your .155 is from a minimum to a maximum. Assuming the same speed, it will take another .155 s to travel from the maximum back to the next minimum.....so you would need to take Kendra's answer and multiply it by 2, which would be 1.686 m.

 

Hope this helped

Answer 2

Use

 

λ = v/f = vT

 

By the definition of period T, you are given that HALF of T is 0.115 s, so

 

T = 2(0.115 s) = 0.23 s

 

Then

 

λ = vT = (7.33 m/s)(0.23 s) ≅ 1.686 m

 

Note the amplitude does not matter in this problem.

Answer 3

I think you have the given values mixed up. The amplitude, wave speed and period are given. You're asked to find the wavelength, λ.

 

A = 0.0800 m

v = 7.33 m/s

T =0.115 s

f = 1/T

 

wavelength, λ = v/f

λ = (7.33 m/s)*(0.115 s)

λ = 0.8430 m

 

** EDIT: The period of the wave is 2 * 0.115 seconds, the time it takes to return to the same position so the wavelength will also be 2*0.8430 m = 1.686 m;