Electricity Flashcards
How to find the voltage between 2 points, A and B, which are in parallel. How does increased internal resistance affect this
Find the voltage at point A by finding the voltage at the components next to it and seeing how much voltage would be left at A. Do the same for B
Subtract these 2 values to find the potential difference.
Increasing the internal resistance would decrease the pd at both points so the ratio may change but the pd could also stay the same if A - B stays the same
Watch MrNagaphysics video if still confused
Does the total resistance of the circuit include internal resistance
Yes, add this at the end
Define EMF
The electrical energy produced by the battery coulomb of charge passing through the battery
What is the breakdown voltage
Very high negative voltage, where negative current can flow through the diode, in the reverse bias
Why does a energy efficient superconductor reduce co2 emissions
Less fuel needed to produce the same energy
What is a potential divider
Resisters in series CONNECTED TO A VOLTAGE SOURCE used to produce a required pd
Why does temperature increase cause resistance to decrease in a thermistor even though the ions still resist electrons more as temp increases
Charge carriers are released, this effect overwhelms the effect of more collisions with ions
How does a blown bulb in parallel affect resistance of the circuit
Means no current can flow through that branch of the circuit so the new circuit is series, if you forget the other branch. Resistance in series is greater than resistance in parallel so the resistance of the circuit will increase
How would you find the resistance of a whole cable given the resistance of 1 strand
resistance of 1 strand/ number of strands in a cable because more strands means more charge can flow at once, which decreases resistance
