Chapter 10: Electricity and Circuits Flashcards
What is current and it’s equation? What are the units?
The net movement of conductive electrons.
I=(Charge)/Time
Amperes
What makes a current move though a wire?
Either the potential difference (emf) at the ends of the wire or the electric field present within the wire.
What prevents current from moving within a wire?
Resistance measured in ohms can be found by voltage/current
What is another way to calculate resistance?
R=(p)(L/A)
What is ohms law?
Voltage=(resistance)(Current)
How to calculate resistors in series?
Simply adding them altogether
How to calculate resistors in parallel?
Taking the product of both, and then divide by the sum of the two. can only do two at a time
What is the difference between DC and AC?
DC allows for the consistent voltage and current. AC allows for various voltage and current to be supplied.
How does current move? Electrons?
Electrons move from negative to positive, but current move in the opposite direction
What happens when you add resistors in series?
voltage must add together but current is constant
What happens when you add resistors in parallel?
voltage is constant, but the current must add together
What are kirchoff’s rules?
That if one battery is present the voltage though resistors in series must add up to the total.
2. If resistors in parallel the current must add together to equal what came in.
What is the power of a resistor? Power of a battery?
Resistor= I^2R while battery is (IV)
How to calculate energy
power*time
What is the equation of capacitance? Units?
Charge *voltage (farad)
How to calculate capacitance?
(Eo)(A/d) where area is directly proportional and distance is inverse.
What is Ed’s formula?
V=E*D
What are two things to note about capacitors?
Create a uniform electric field within the two plates, and they do in fact store charge.
How to find the energy stored in a capacitor?
PE= (1/2)Q*V
What is a dielectric?
An insulating substance that goes between the two capacitor plates to increase the capacitance. (by a factor of K)
What happens when you place a dielectric when the capacitor is charging?
No effect on the potential energy, and no effect on the electric field.
Does increase the charge by a factor of K
What happens when you place a dielectric when the capacitor is disconnected?
The voltage drops by a value of K along with the electric field value.
There is heat released as a result of PE lost.
Calculation of capacitor in series?
1/C1+1/C2
Calculation of capacitor in parallel?
Simply add them all together
Finding voltage and current with an AC setup?
V/sqrt2 and I/sqrt2
