Understanding Standing Waves at 60 Hz and 0.4 m Wavelength

[Unemployed]

Homework Statement

Draw a sketch of of a standing wave created by a string fixed at two ends, the frequency is 60 Hz, the wavelength is 0.4 m. Draw a profile with times t=0, T/4, T/2, 3T/2

Homework Equations

period= 1/frequency,

The Attempt at a Solution

i know that at t/4, you will have a quarter of a wavelength going down the string at 1/240 seconds, but does it get reflected back? or is it just a quarter bump gowing towards the end, and the rest of the string is straight?

 

[Andrew Mason]

Homework Statement

Draw a sketch of of a standing wave created by a string fixed at two ends, the frequency is 60 Hz, the wavelength is 0.4 m. Draw a profile with times t=0, T/4, T/2, 3T/2

Homework Equations

period= 1/frequency,

The Attempt at a Solution

i know that at t/4, you will have a quarter of a wavelength going down the string at 1/240 seconds, but does it get reflected back? or is it just a quarter bump gowing towards the end, and the rest of the string is straight?

A standing wave has fixed nodes so the wave does not travel. Hence the name "standing". It just goes up and down in between nodes.

If it is fixed at two ends, the ends must be nodes. The lowest frequency mode of vibration of this standing wave is with the ends forming the first two nodes of the standing wave - ie. 1/2 wavelength. How long would the string be?

AM

 

[Unemployed]

This is from a lab, in which i calculated the wavelength to be 0.4 m from this equation:

L=n*wavelength/2

therefore wavelength = 2L/n=.4
L= 1 m
n = (5 in the non-makeup lab)

The frequency gotten from the experimental was 60Hz

which if you plug into the equation v=f* wavelength
v is given as 23.5, you get about .4 for the wavelength
Makes sense about the standing wave.

A period is what it takes for 1 wave to travel a whole wavelength, which here is 1/60 seconds.

but if you draw something at less than a wavelength, doesn't the pulse need to travel down the whole second to the full reflected wave?

If it only travels for 1/240th of a second, do you just draw a line at the quarter wavelength mark? How does it look?