The Relationship Between Length and Frequency in a Simple Pendulum

AI Thread Summary
Cutting the bottom half of a meter stick pendulum affects its frequency, but the relationship is not as straightforward as doubling the frequency. The frequency of a simple pendulum is determined by its length, with the formula f = (1/2π)√(g/L), where g is the acceleration due to gravity and L is the length of the pendulum. When the length is halved, the frequency increases, but not necessarily to twice the original frequency; it actually increases by a factor of √2. The confusion arises from comparing the pendulum's behavior to that of a tuning fork, which operates under different principles. Understanding the correct equations for pendulum motion is crucial for accurately determining frequency changes.
marine192
Messages
1
Reaction score
0
A meter stick swinging from one end oscillates with a frequency f0. What would be the frequency, in terms of f0 , if the bottom half of the stick were cut off?







Based on a experiment we did in class with tuning forks the frequency should be twice as much if the length were reduced by half but when I enter that in for the answer it comes up as incorrect. Today in class we went over that a frequency remains the same when transferring between mediums but there is no transfer here, just a shortening of length so that shouldn't have any effect on it. I can't figure out where I am going wrong with this.
 
Physics news on Phys.org
welcome to pf!

hi marine192! welcome to pf! :smile:

a pendulum isn't remotely like a tuning fork

(btw, http://en.wikipedia.org/wiki/Tuning_fork#Calculation_of_frequency" says frequency of a tuning fork is inversely proportional to length squared, but there's no reference for it :frown:)

do you know any equations that may help to describe the motion of a pendulum?
 
Last edited by a moderator:
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top