Finding Mass for a Standing Wave in a Horizontal String

MK7_Ironman
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Homework Statement


One end of a horizontal string of linear density 4.7 multiplied by 10-4 kg/m is attached to a small-amplitude mechanical 58 Hz vibrator. The string passes over a pulley, a distance L = 1.50 m away, and weights are hung from this end, Fig. 11-48. Assume the string at the vibrator is a node, which is nearly true.

11_48.gif


What mass must be hung from this end of the string to produce a standing wave with the following number of loops?

a). one loop: ?
b). two loops: ?
c). five loops: ?

Homework Equations


I don't know how to do this problem that is why I'm asking.


The Attempt at a Solution


I really don't know where to start that is why I need help please!
 
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Welcome to PF :smile:

You'll have to come up with something before receiving help here. How about finding what equations have something to do with wave velocity, wavelength, and frequency?

Also, they gave you the linear density of the string in the problem statement. There's probably an equation that uses that, which will be useful here.
 
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