Finding string mass from pulse speed and tension

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Homework Statement


A 1.50-m-long string is under 30.0 N of tension. A pulse travels the length of the string in 50.0 ms.

Homework Equations



v of string = sq rt of (Tension of string/ string's mass-to-length ratio)

string's mass to length ratio= m/L

The Attempt at a Solution



So, the pulse takes 50.0 ms to travel through 1.5 m of string. So, the velocity of the pulse is 1.5 m/.050 s.

V= 1.5/.050 = 30 m/s

Now that I know the velocity, I can use the V of string equation.

V[tex]^{2}[/tex]= T/[tex]\mu[/tex]
[tex]\mu[/tex]= T/V[tex]^{2}[/tex]
[tex]\mu[/tex]= 30.0N/ (30m/s)[tex]^{2}[/tex]
[tex]\mu[/tex]=.033

[tex]\mu[/tex]=m/L
[tex]\mu[/tex]*L=m
.033*1.5=m
m=.049995 or .05 g

However, master physics disagrees with this answer. What am I doing incorrectly?
 
Last edited:
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The answer should be in kilograms not grams.
 
Actually, the unit they want mass in is g. Sorry. Forgot to put that in there.
 
I was not clear explaining what I meant. The answer that you got, 0.05 is in kilograms. You need to convert that to grams. Did you enter 0.05?