PHYSICS LAB MANUALS

Damped Oscillations

In this experiment three physical quantities are measured

Table II : Details of Physical quantities to be measured


S.No

Physical quantity

Independent /

Dependent

Measured

With

Measuring instrument’s

Minimum

Maximum

Least count

1

time

Independent

Logger Pro

0



2

Angle

Dependent

Logger pro




3

mass

Independent

Weighing machine





  1. Measure the spring constant of individual springs and for combined springs. Plot the three sets of the data on the same graph.
  2. Arrange retort stand bases, rods and horizontal beam as shown in fig - 1.
  3. Hang the springs on the horizontal beam and attach a teflon strip to the other end of the springs.
  4. Tie a thread at the centre of the Teflon sheet.
  5. Fix the rotary motion sensor such that the thread just touches the outer side of the rotary motion sensor
  6. Pass the thread over the larger pulley
  7. Hang weights about 100 gm using a weight hanger to the other end of the thread.
  8. Take liquid medium in a beaker and place it under the weights. Ensure that the mass is completely immersed in the liquid medium.

    Rotary sensor connected a computer is used to record the motion. Refer to a separate sheet provided to learn how to use the computer interface.
    When clear damped oscillations are observed -
  9. Note down the time and angle values corresponding to consecutive maximas.
  10. Repeat the steps for different mediums. Make different table for different mediums.
  11. Plot a graph of v/s time for all media in a single graph and obtain the value of damping factor using the slope.

Table III : Observation

S.No.

Time

Ai

Reduction ratio

AiA1

lnAiA1


s

radians

-

-

1





2