• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Determination of moment of inertia of a uniform rectangular bar and a connecting rod using the trifilar suspension, and by swinging the connecting rod as a compound pendulum.

Extracts from this document...


The Trifilar Suspension Tutor : Dr. Yan Name : Manilka Abeysuriya Course : Aeronautical Engineering Group : A - 1 Date : 27 / 01 / 2003 Title : Determination of moment of inertia of a uniform rectangular bar and a connecting rod using the trifilar suspension, and by swinging the connecting rod as a compound pendulum. Introduction : Moment of Inertia can be described as a measure of "unwillingness to change the current motion" of a certain body of mass. In the experiment, the main objective is to find the moment of inertia of a uniform body and an irregular shaped body. Toward achieving this First the center of mass of the bar and the connecting rod was found by balancing them on a knife-edge. Then the bar was placed on the trifilar suspension which is a circular platform suspended by three equally spaced wires of equal length, such that the center of mass of the rod is over the center of the circular platform. Then the whole system is given a small angular displacement, and the periodic time for the oscillations is determined by measuring the time taken for 20 oscillations. ...read more.


I = For the connecting rod (2nd suspension) I = Discussion : The equation 1 is accurate only for oscillations with small angular displacements. If this displacement is considerably large an error could occur in the final results due to this reason. And also when using the trifilar suspension the center of mass of the object under consideration should be right over the platform. Other wise a additional moment of inertia of the system will cause a increase of the result, actually expected. When measuring the time an error is always possible in the measurement due to differences in human reaction time. Analysis of Error, When I = 0 and M = 0, From equation 1, Error in , = = 7.62 x10-3 = 7.62 x10-3 x = For the uniform rod, Let m = ( M + Mo ) Then, m = (1125 + 1954.8 ) x 10-3 kg = 3.080 kg Error in m is, = 1.01 x 10-6 kg From equation 1, Let Error in, = kgm2 = 5.1 x10-5 x = Error in I , kgm2 = For the theoretical calculation of I for the uniform rod, From equation 2, Let p = I2 + w2 = (0.25452 +.0385 2) ...read more.


s From Equation 1, Dimensions for uniform rod, Length 254.5mm Width 38.5mm Mass 1954.8g For the oscillations of the system rod and the trifilar suspension, T1 2.056 s T2 2.050 s T3 2.066 s Average - T 2.057 s From Equation 1, Theoretically, Equation 2 For the connecting rod, Mass 1848.52 g T1 2.918 s T2 2.923 s T3 2.922 s Average - T 2.921 s Using Equation 1 for the system of trifilar suspension and the connecting rod, When the connecting rod was suspended by a end let to swing the moment of inertia of the rod about the axis through the point of suspension is given by, ................ Equation 3 Where, T - periodic time M - mass G - acceleration due to gravity l - distance from the point of suspension. Using the parallel axes theorem, Iy1y1 = Iyy + Md2 Iyy = Iy1y1 - Md2.............Equation 4 When l = 236 mm, T1 0.9980 s T2 1.084 s T3 1.072 s Average - T 1.051 s From equation 3, From Equation 4, When l = 100 mm, T1 0.9950 s T2 1.030 s T3 1.040 s Average - T 1.022 s From equation 3, From Equation 4, ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our University Degree Mathematics section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related University Degree Mathematics essays

  1. History and Social Context of Mathematics.

    As we have already seen the theorem which bears his name was in use previously by the Babylonians, but with one important omission. The Babylonians established the rule empirically, that is to say, by discovering that for all the right-angled triangles they tried, the rule held.

  2. The trifilar suspension is used to determine the moments of inertia of a body ...

    0.013 kg/m Inertia of rod (Hanging method) 0.042 kg/m Discussion In this experiment two different sets of readings where gathered and recorded. Both the bar and the rod where tested by the trifilar method. However the rod was placed under one more test, the knife edge, results for these experiments can be seen on table one.

  1. Case Analysis: Forecasting Food and Beverage Sales

    Hence, to understand and measure these components, the forecast procedure involves initially removing the component effects from the data (decomposition). After the effects are measured, making a forecast involves putting back the components on forecast estimates (recomposition). Pursuing this can help Karen take a proper judgment.

  2. This experiment is to measure and calculate the partial molar volumes of sodium chloride ...

    The pycnometer is then cleaned and dried thoroughly. Once it was dried, it was then weighed empty and this weight was recorded as the WE. This procedure was done twice at both the beginning and end of the lab period.

  1. Investigating the affect that Body Mass Index and Waist-to-hip Ratio has on the Perception ...

    The overall conclusion was that over the last three decades a significant change in the idealized female body shape has occurred. However, later studies showed that Morris et al results were inaccurate and that when the actual WHRs were computed they remained within a feminine 0.68-0.72 range thus, clearly showing

  2. Pythagoras’ Theorem.

    Whether someone from the school or Pythagoras himself found the proof can't truly known. Hence the philosophy of Pythagoras is known through the work of his disciples. The school did make several contributions to mathematics. Pythagoras believed that all relations were based on number relations.


    The potential field method has a low computational requirement. In contrast, global methods need complete information about the world and hence would require relatively large computational power. The probabilistic roadmap which is a skeletonization method offers more possible routes and thus deals better with wide open spaces. The graph is created by randomly generating a large number of configurations, and discarding those that do not fall into free space.

  2. Logistics equation. This coursework relates to an investigation and description of the systems ...

    in the form of data has risen exponentially and being able to secure your flow of data has become a necessity, it is this desideratum that brought about encryption and its uses/ methods. Take the military for example, in war time situations communication is 'sine que non' for the military,

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work