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Pendulum Experiment (1 Viewer)

C20H25N3O

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Does this experiment help distinguish between non-inertial and inertial frames of reference?

Aim:
To calculate and the rate of acceleration due to gravity by investigating the gravitational effects on the oscillatory motion of an average pendulum.

Apparatus:
  1. Retort Stand
  2. Clamp
  3. Boss Head
  4. String 1- meter
  5. Mass Carrier
  6. Mass 50g
  7. Metre Rule
  8. Stopwatch
  9. Large Protractor


Method:
  1. Set up the apparatus as shown in the diagram above.
  2. Collect a mass carrier and tie it strongly to a string.
  3. Pick up the mass carries by the string and have another member of the group carefully measure 1 of the string starting from the base of the mass carrier.
  4. Record the length of the pendulum. Attach the string to the clamp really tightly and ensure that you still have 1 meter from the top to the bottom of the string.
  5. Ensure that the vicinity is free of any obstructions to the swinging pendulum.
  6. If necessary place a g-clamp or excess weight on the retort stand to stop the retort stand from absorbing the motion energy of the pendulum by vibrating.
  7. Reset all stop watches and gently move the pendulum from equilibrium to a measured distance of 15º or less using a large protractor. Ensure the angle of deviation from the vertical is measured properly and is kept the same throughout all trials.
  8. Carefully release of the mass from the deviated angle and allow it to swing for 2-3 swings and lose some of the vibrations that may have been transferred.
  9. Activating the stopwatch as the string oscillation commences a new period.
  10. Continue timing the pendulum until it has moved through 10 complete oscillations (periods) and record the times.
  11. Repeat steps 3 through 9 a total of 5 more times. However before each new set shorten the string by 10 cm of its length. Ensure that the deviation angle is controlled for constancy through all trials.
  12. Use the equation g = 4π2l/T2 and determine g for each result and finally perform necessary calculation to determine the average.
  13. Represent the results graphically by plotting a graph for period squared vs. length. Draw the line of best fit.
  14. Use the gradient of the line and sub into equation g = 4π2 1/m
  15. Write a conclusion for the experiment and outline which final result is valid and why this is so.
 
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Parvee

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I don't even know, I'm suppose to write up an experiment that allow me to distinguish between non-inertial and inertial frames of reference and perform it in class. Any suggestions?
the experiment you provided is to calculate g

To distinguish inertial and non-inertial frames you would have a pendulum inside a vehicle. Traveling at constant speed (ie non-accelerating) the pendulum will not move ->inertial frame of reference. If the vehicle accelerates the pendulum will move back -> non inertial.
 

C20H25N3O

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the experiment you provided is to calculate g

To distinguish inertial and non-inertial frames you would have a pendulum inside a vehicle. Traveling at constant speed (ie non-accelerating) the pendulum will not move ->inertial frame of reference. If the vehicle accelerates the pendulum will move back -> non inertial.
How do I turn this into an experiment I perform in class?
 

Parvee

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How do I turn this into an experiment I perform in class?
um have a student carry a mass tied to a string.
if they walk at a constant pace the pendulum will not move ->inertial f.o.r
if the walk at an increasing pace the pendulum should tilt back -> non-inertial f.o.r

this is kinda hard to do since it would be hard to walk exactly at a constant pace
 

C20H25N3O

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um have a student carry a mass tied to a string.
if they walk at a constant pace the pendulum will not move ->inertial f.o.r
if the walk at an increasing pace the pendulum should tilt back -> non-inertial f.o.r

this is kinda hard to do since it would be hard to walk exactly at a constant pace
yeah, I don't know but then again I could do that and say that the experiment is not valid as the person is not walking at a constant pace. I don't know what to do, any advice?
 

anomalousdecay

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You can have a cart with a ceiling which you can hang a pendulum onto. Then you can give it a push and let it move uniformly (ideally this will give as close to a constant pace as possible, neglecting friction), and then try again with pushing it by hand all the way. You will see the pendulum tilted the second time as Parvee said, but not the first time.
 

C20H25N3O

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You can have a cart with a ceiling which you can hang a pendulum onto. Then you can give it a push and let it move uniformly (ideally this will give as close to a constant pace as possible, neglecting friction), and then try again with pushing it by hand all the way. You will see the pendulum tilted the second time as Parvee said, but not the first time.
I need a more simple experiment because I'm not bringing a cart into school... is there any other experiment that I can perform that help distinguish between non-inertial and inertial frames of reference?
 

anomalousdecay

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I need a more simple experiment because I'm not bringing a cart into school... is there any other experiment that I can perform that help distinguish between non-inertial and inertial frames of reference?
Put water in a plastic see through container, put it on some sort of trolley or something (I guess you can improvise with this using a toy or something) and do the same thing as I described. If there is no force acting on the system (inertial frame) then you will observe the water's surface to be quite still. If there is a force (as you push it along) (non-inertial frame) then you will exhibit that the water will tend to accumulate more onto one side of the container.
 

C20H25N3O

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Put water in a plastic see through container, put it on some sort of trolley or something (I guess you can improvise with this using a toy or something) and do the same thing as I described. If there is no force acting on the system (inertial frame) then you will observe the water's surface to be quite still. If there is a force (as you push it along) (non-inertial frame) then you will exhibit that the water will tend to accumulate more onto one side of the container.
Dude, you're god thanks. sorry for the late reply been doing work.
 

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