PASCO ME-9215B Photogate Timer - Manual (Page 42)

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Photogate Timer 012-06379B
®
Part 2: Conservation of Mechanical Energy
The table below present theresults for the conservation of
energy with the pendulum dropped at varying heights.
L = 100 cm
ΔΔΔΔΔd = 2 cm
Mass = 175.2 g
After repeated trials, these are the best results that can be
obtained by means of a Photogate Timer. The accuracy
of the experiment increases with an increase in the preci-
sion of measurements of angles and lengths. To get even
better accuracy, you may consider using the Computer
Photogate Timing System.
θ Δh
t
Δu
E
k
% of diff.
(deg) (cm) (s) (J) (J) (%)
15 3.41 0.00 0.06 0.07 -11.97
20 6.03 0.00 0.10 0.11 -3.50
25 9.37 0.00 0.16 0.16 0.00
30 13.40 0.00 0.23 0.21 6.96
35 18.08 0.00 0.31 0.30 2.55
Notes - Questions
c
From the graphs, there exist a linear relationship
between period and the squared root of the length of
oscillation. This relationship remained unchanged
despite changes in mass of pendulum.
d
No. For small oscillation, period of oscillation is
independent of mass.
e
Yes.
f
No. During the repeated cyles of conversion of energy
from purely potential to kinetic energy, frictional and
gravitational forces continued to act on the pendulum to
convert some of the energy to other forms.