How do I calculate the frequencies of the following?

  • Thread starter Thread starter riseofphoenix
  • Start date Start date
  • Tags Tags
    Frequencies
AI Thread Summary
To calculate the tension required for a steel piano wire to produce a fundamental frequency of middle C (261.6 Hz), the tension must be approximately 985 N. For the human ear canal, modeled as a tube closed at one end, the fundamental frequency can be determined using the formula f = TM/L√2L. The discussion highlights the calculations involved in determining these frequencies based on physical properties like length and mass. Accurate calculations are essential for understanding sound production in musical instruments and human hearing sensitivity. The conversation emphasizes the importance of applying the correct formulas for precise results.
riseofphoenix
Messages
294
Reaction score
2
7. A steel wire in a piano has a length of 0.9000 m and a mass of 4.000 10-3 kg. To what tension must this wire be stretched so that the fundamental vibration corresponds to middle C (fC = 261.6 Hz on the chromatic musical scale)?


8. The human ear canal is about 2.6 cm long. If it is regarded as a tube open at one end and closed at the eardrum, what is the fundamental frequency around which we would expect hearing to be most sensitive?
 
Physics news on Phys.org
Do I use:

f = TM/L√2L
 
For the first one I got T = 49888794.74
 
Oh wait the first one is T = 985 N
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top