Preliminary Yearly Physics Exam (1 Viewer)

[AreYouAlright?]

The following question was a multiple choice one on my preliminary Physics exam, i have shown the answer i obtained however my Physics teacher has marked it wrong and i have shown her answer- could some one please tell me if i am correct or why i am incorrect... thankyou

 

[tigerchenyanhu]

of course the phyics teacher is correct

because the resultant 2 waves must be connected . they won't be separated by any interval between them

 

[AreYouAlright?]

Where did u get that from?

Where does it state that the resultant two waves must be connected? Hmm... if that's the case it would of helped if i knew that, that defies common sense though. Are you sure?

 

[tigerchenyanhu]

by calculating

as shown by ur calculation on the paper ,focus on the left starting point of the left wave and the right ending point of the right wave . after 0.6s ,they will be at the same point hence the resultant 2 waves must be conneted .

 

[AreYouAlright?]

I still don't see it...

How does that work if i look as they are both moving in opposite directions i look at the starting point of the crest on the left it will move 1.2m to the right which would be the end of the trough on the right and at the same time the starting point of the trough on the right will move 1.2m to the end of the crest... how do they touch? doing that there is still the .4m in the middle can u draw a diagram in paint?

 

[tigerchenyanhu]

u are quite right

sorry i was just so careless that i did not notice that. i think u are right mate

 

[AreYouAlright?]

lol

Thankyou mate i thought it was just me going crazy there for a second hehe but perhaps not.. i'll have to follow it up