Test 2 Flashcards
What does Ohm’s law state?
Current is directly proportional to voltage and inversely proportional to resistance
What is constant, not changing depending on voltage in Ohm’s law?
Resistance
Ohm’s Law Formula
I=V/R, V=I*R, R=V/I
What happens to the voltage in a parallel circuit?
The voltage of the supply is given to each load
What happens to the current in a parallel circuit?
All loads add up to the current
What happens to the current in a series circuit?
All loads have the total current
What happens to the voltage in a series circuit?
All loads add up to the total voltage
Power formula
Joules/time, VI, V^2/R, I^2R
What is kW/h (kilowatt-hour)?
How many kilowatts are used per hour (1.0 kilowatts per hour is 1.0kw/h, 60w per hour is 0.06kw/h)
Efficiency formula
|Power Out/Power In|
What usually causes loss in efficiency?
Heat
How to troubleshoot a series circuit with only an ohm meter
Narrow down by measuring half of the set over and over again -> If resistance is present, current is flowing, if not, current is not flowing
What is a series circuit?
Any electrically conducting pathway with the entire current flowing through each component
What is a parallel circuit?
Any electrically conducting pathway with branching paths
Formula for total resistance in series circuit?
R_T = R1 + R2 + … + R_x-1+R_x
Formula for total resistance in parallel circuit?
1/R_T = 1/R1 + 1/R2 + … + 1/R_x-1 + 1/R_x
How do you measure current in a series circuit?
Turn off circuit, break circuit, insert mA meter -> positive of meter goes to power supply, negative goes back to circuit
When measuring resistance in parallel, what should the reading be?
Less than the value of your smallest resistor
How do you measure current in a parallel circuit?
Turn off power, break one of the resistors out, put positive on broken resistor and negative on unbroken resistor, switch broken resistors for measuring each one
