PASCO SF-8616_8617 COILS SET - Manual (Page 10)

scientific 8
012-03800A
Note: Other configurations can be investigated once you have the E-shaped core. At
your instructor’s direction, investigate other methods of arranging the primary and
secondary coils.
8. If there are more than one PASCO Coils Sets in the laboratory, set up a series of transformers
such as the one diagrammed below in Figure 4. Measure input and output voltages, input and
output currents at various places in the chain. Keep careful track of your measurements and
draft your observations based on these measurements.
Primary Secondary Primary Secondary
Input Output
Figure 4
Analysis
1. Calculate the quantities asked for in Table 2.2. Note the suggestion at the bottom of the page.
If you were able to carry out the modification in step 7, a separate data table should be
constructed.
2. What relationship exists between the output current and the input current for different coils
given a constant load resistance? How does varying the load resistance change the output
current/input current relationship for a given combination of coils? Is the effect the same for
all combinations? Elaborate and make an educated hypothesis on why your experiment
behaved the way it did.
3. The ideal voltage gain is equal to the number of turns in the secondary divided by the number
of turns in the primary. How did the actual voltage gain (Vout / Vin) compare to the ideal?
4. Ideally, transformers convert alternating current from one voltage to another with very little
power loss (almost 100% efficient). Looking at your power gain (Pout / Pin), how did your
transformers do compared to ideal transformers?
5. What combination of voltage and current is gained by having few coils of wire in the secon-
dary? (step 6)
6. Analyze the behavior of the coils in the E-shaped core, and compare this to the U-shaped
core. Is there a distinct advantage of one over the other? Why? Can an advantage gained be
further enhanced by other changes? What might they be? (step 7)
7. If you began and ended with the same number of turns in your coils (step 8), how did the
input and output voltages compare? How did the input and output power for the total combi-
nation compare? Were principles you experimented with previously in evidence during this
part of the lab?