Solving the Tuning Fork Problem: Maximum Speed and Kinetic Energy

AI Thread Summary
The discussion revolves around calculating the maximum speed of a tuning fork's prong and the kinetic energy of a fly perched on it. The maximum speed was calculated as 1.48 m/s using the formula V = ω * Amplitude, where ω is derived from the frequency. For the fly's kinetic energy, participants debated whether to use the total mechanical energy formula or just the kinetic energy formula, with a focus on ensuring the fly's mass is in kilograms for accurate calculations. The consensus is that the fly's kinetic energy is directly related to the fork's maximum speed. Accurate unit conversion is crucial for obtaining the correct kinetic energy value.
lollypop
Messages
33
Reaction score
0
hi:
my questions says the following:
A tuning fork labeled 392 Hz has the tip of each of its two prongs vibrating with an amplitude of 0.600 mm.
What is the maximum speed of the tip of a prong?

for this part i found omega= frequency*2pi
then plugged that in V= omega*Amplitude, so my answer is 1.48 m/s.

Now in the second part of the problem they ask:
A housefly with mass 0.0270 g is holding on to the tip of one of the prongs. As the prong vibrates, what is the fly's maximum kinetic energy? Assume that the fly's mass has a negligible effect on the frequency of oscillation.

is this the formula i have to use ?--> E=.5mv^2 + .5 kx^2, if it is, please how can i find x ? do i get k from omega = sqrt(k/m). I'm not sure what to do for this part. which equation should i use?
:confused:
 
Physics news on Phys.org
Why would you include the potential energy of the fork? That's got nothing to do with the fly's kinetic energy.

cookiemonster
 
i don't know which one to use, using just .5mv^2 gives me the wrong answer, is there any other formula i may use?
 
The idea is that the velocity of the housefly is the same as the velocity of the tuning fork, and therefore the kinetic energy of the housefly is proportional to that of the fork. When does the fork have the maximum kinetic energy? Can you find its velocity at that point?
 
lollypop said:
i don't know which one to use, using just .5mv^2 gives me the wrong answer, is there any other formula i may use?

You have the speed correct. Did you convert the flies mass to kg. so that you get the kinetic energy in Joules? (Or convert speed to cm/s and use the mass as given in grams to get the kinetic energy in ergs.)
 
What is the formula for acceration? For velocity is omega * amplitude
 
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