Beats using Tuning Forks with and without clamps

1. Apr 27, 2010

seacow90

1. Assuming the pitchfork is the same in the following three cases, put them in order of decreasing frequency (e.g., a>b>c)

a. pitchfork with clamp on top

b. pitchfork without clamp

c. pitchfork with clamp on the middle

(Hint: Although it is not exactly like a pendulum (string + mass ball), you may want to make analogy of the two, and think of the clamp as the mass ball, and its distance to the base of the pitchfork as the length of string. What happens to the frequency of a pendulum if the length of string is increased?)

1. Assuming the pitchfork is the same in the following three cases, the height frequency would the pitchfork with the clamp in the middle, followed by the pitchfork without a clamp, and the least frequency will be the pitchfork with the clamp on top. Using a pendulum and mass analogy, the clamp in them middle produces the fastest frequency because now the length that that the pitchfork has to move has been greatly reduced by half. The clamp on top of the pitchfork will produce the slowest frequency, as the length is still the same as the pitchfork without the clamp, but mass has been added to the pitchfork.

2. If the frequency of the pitchfork is f without clamp, and fc with clamp, what is the frequency of the beat generated? (beat frequency must be positive!)

The beat frequency is fb= | fc-f |. The absolute value is used to always get a positive frequency as the position of the clamp on the pitchfork can produce a frequency that is either higher or lower than that of the frequency of the pitchfork without a clamp.

3. Which of the following would generate a better-looking beat on the computer screen? Briefly explain why (1 short sentence)

a. strike harder on the one without clamp

b. strike harder on the one with clamp

c. strike both with equal strength

d. it doesn't matter

(Hint: What would you get on the screen if one of the pitchfork is not so much hammered as is barely touched? In particular, would you get a beat?)

Striking both with equal forces will produce the best beat on the computer as the amplitude of the sound waves will be the same for both the tuning fork with the clamp and the tuning fork without the clamp.