Reducing Wave Speed by Half: Understanding the Equation and Its Components

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Reducing wave speed by a factor of 2 means dividing the original speed by 2. In the discussion, the original wave speed is 265 m/s, and the tension, mass, and length of the string are provided. The equation used is v = sqrt(F / (m/l)), leading to a mass calculation of m = (F * l) / v². There is confusion regarding the calculated mass, where one participant expected 15g but arrived at 20g instead. The clarification sought revolves around understanding the implications of reducing wave speed and the resulting mass calculation.
cseet
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Hi all,
can anybody pls explain what is reduce the wave speed by factor of 2?

question:
original v(string) = 265m/s
F (tension) = 500N
m (mass) = 0.005kg
l (length) = 0.7m


Equation:
v = sqrt of [F / (m/l)]
therefore m = (F * l) / v square

but I though reduce speed by the factor of 2 = divided by 2?? pls kindly advise.
thanks
cseet
 
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Reduce by a factor of 2 does mean divide by 2.

cookiemonster
 
Hi Cookiemonster,
that's what I thought, but when I did the equation, the answer I got is 20g but the answer is 15g... can you explain that?
thanks
cseet
 
What exactly is the question? I thought all you asked was what reducing by a factor of 2 meant.

cookiemonster
 
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