What Is the Correct Velocity of the Standing Wave?

AI Thread Summary
The discussion centers on calculating the velocity of a standing wave oscillating at 100 Hz, using the formula velocity = wavelength × frequency. The user initially calculates the wavelength as 20 cm (20x10^-2 meters) and finds the velocity to be 20 meters per second, but doubts the accuracy of this result. Participants point out potential errors, including the need to clarify the wavelength measurement and ensure consistent units throughout the calculation. The importance of accurately representing a full cycle of the sine wave is also emphasized to avoid confusion. Correcting these issues is essential for arriving at the right answer.
Spirochete
Messages
125
Reaction score
0

Homework Statement



The standing wave in the picture is oscillating at 100 Hz. What is it's velocity?


Homework Equations



Velocity=(wavelength)(frequency)

I believe is the equation that applies here.


The Attempt at a Solution



The wavelength from the picture appears to be 20x10-2 meters.

So velocity should equal (20x10-2)(100)= 20 meters per second

But I know this answer is wrong. Where am I going wrong?
 

Attachments

  • standing wave.jpg
    standing wave.jpg
    5.3 KB · Views: 394
Physics news on Phys.org
Spirochete said:

Homework Statement



The standing wave in the picture is oscillating at 100 Hz. What is it's velocity?


Homework Equations



Velocity=(wavelength)(frequency)

I believe is the equation that applies here.


The Attempt at a Solution



The wavelength from the picture appears to be 20x10-2 meters.

So velocity should equal (20x10-2)(100)= 20 meters per second

But I know this answer is wrong. Where am I going wrong?

Why do you say that the wavelength is 20cm? Draw a full cycle of a sine wave -- what does it look like?

Also, be careful with your units. It looks like you are mixing cm and meters in your multiplication and answer...?
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Back
Top