Elenco Snaptricity&reg - Manual (Page 39)

Snappy says: connecting
parts in parallel allows more
current to flow, so it
decreases the overall circuit
resistance.
-38-
Educational Corner:
Project #29
1A
If you add up the current you measured
through circuit branches B, C, and D, it
should be the same as the current you
measured from the batteries. (Your
result may be a little different, because
M5 is a simple meter with low
accuracy.)
Kirchhoff’s Current Law , an
important rule for analyzing circuits,
says that all current flowing into a point
must flow out of it.
(Current
batteries
= Current
lampB
+
Current
lampC
+ Current
LampD
)
The total battery current here is much
higher than in project 13, because this
circuit has several lamps in parallel.
The lamps are acting as resistors,
limiting the flow of electricity in the
circuit. As resistances are added in
parallel, they increase the total current.
1A
Part B
Current Divider
Part C Part D
Electric Paths
B C D
Part A: Push the press switch (S2); the meter measures the
current from the batteries (B3).
Part B: Swap the location of the meter with the 3-snap wire
marked “B” (“+” side towards the lamp). Push the switch to
measure the current through circuit branch “B”.
Part C: Swap the “B” location of the meter with the “C” 3-snap.
Push the switch to measure the current through the “C” branch.
Part D: Swap the “C” location of the meter with the “D” 3-snap.
Push the switch to measure the current through the “D” branch.
Operation
The current from the batteries splits up between the three lamps,
because they are connected in parallel.
Description
Build the main circuit and set the meter (M5) on the 1A setting.
Assembly