PASCO ME-6694 TORSION PENDULUM - Manual (Page 15)

012–06339A Torsion Pendulum
11
Table 1.3
Calculation of I
disk and cylinder
from the torsional spring constants
of wires ( κ )
Part C: Determining the Moment of Inertia (I) of a Disk and Cylinder Using Two Methods
1. Place the ring of the Mini-Rotational
Accessory on the disk (Figure 1.3).
2. Repeat steps 2–6 of Part B. Record your
data in Table 1.3.
3. Change the wire to the 0.047 inch
diameter wire and repeat steps 2–6.
4. Change the wire to the 0.032 inch
diameter wire and repeat steps 2–6.
5. Measure the mass and R
1
and R
2
of the
cylinder and record below.
wire diameter κ (N·m) T I
disk and cylinder
(inches) (from part A) (s) (kg/m 2 )
0.032
0.047
0.062
Figure 1.3
Experimental setup for Part C
cylinder from Mini-
Rotational Accessory
disk from Mini-
Rotational
Accessory
3-step pulley
R
2
R
1
mass of cylinder (kg) ____________
R
1
(m) ____________________
R
2
(m) _ ___________________
I =
1
2
m(R
1
2 +
R
2
2
)
I
disk and cylinder
(using mass and radius measurements) _____________
Compare the values of calculated I
1. Calculate I using both formulas:
and record above.
I =
1
2
mR
2
+
1
2
m(R
1
2 +
R
2
2
) I =
T
2
π
2
κ and