Transverse longitudinal waves : slinky lab

[jnimagine]

transverse longitudinal waves : slinky lab!

so this lab we did is called the transmission and reflection of a one-dimensional transverse wave...
1. we created a transverse pulse from one side and observed a point near the middle of the spring as the pulse passed...
- > so i wrote that it just moves in the shape of the pulse... but... apparently if you stuck a crunched up paper in the middle of the slinky, something's supposed to happen to it... what kinda motion should happen?

2. does the amplitude of a pulse change as the pulse moves from one end of the spring to the other? why?
-> i said no it doesn't change... but... i wasn't quite sure by looking at it...

3. When u generate two pulsees, one right after the other, the distance between them stayed the same... what does this tell us about the speed of the pulse? and if u generate one small and one large pulse one after the other, how does the amplitude of each affect its speed?
-> well we know that the pulse moves in constant speed but I'm not sure if the amp would affect it...

4. How is speed of each pulse affected by the change in the tension of the spring?
-> i said small pulse dies quicker and the big pulse is faster

5. How is the reflected pulses from the fixed end different from the original pulses..?
-> i said their shapes are just opposites. so when there was a trough in original pulse, there was a crest in the reflected..

6. we suspended the spring vertically from the a high point and generated a transverse pulse at the top of the spring. Is the pulse inverted when it is reflected from the free end of the spring?? and we had to compare the properties of fixed-end and free-end reflections.
- > I'm not sure about the first part of the question but for the second part, i just put the same answer as #5

we also did a lab with longitudinal wave.
1. so we put masking tapes at six equally spaced points along the spring and at one end we compressed 10 coils. then we released the coils and observed the motion of the masking tape tabs.
-> from what i saw... i just noticed that the tabs moved forward but... nothing else..T.T

2. and what was the motion of the tabs when you compressed the spring?
-> same as #1, we only noticed it go forward and that's it...

3. what was the motion of the tabs when you rarified(?) it?
-> I'm not sure about this one...

4. when you move your hand back and forth quickly at a uniform frequency, what was the motion of the tabs??
-> ...

5. How many complete vibration of your hand do u think is need to produce one compression and one rarefaction?
-> ...



i know this is a lot of questions... but i just need some explanations about the questions from the above...
if anybody can help me with even a few of the questions, i'd really appreciate it
Thanks a lot

 

[kuruman]

Yup, them are a lot of questions. Let's start with the first item. You set up a transverse wave in the sliky and you watched it propagate. You say, "... but... apparently if you stuck a crunched up paper in the middle of the slinky, something's supposed to happen to it... what kinda motion should happen?" Did you stick a crunched up paper in the middle of the slinky? If yes, what kinda effect on the pulse did you observe? If no, why not?

I sense that you were not paying attention to what you were supposed to be observing and I cannot tell you what you should have seen because I was not there. I am better at explaining why and how something happened after you tell me in some detail what it was.