P2 Flashcards
What is a cell
A component that Pushes current around a circuit
What is a current
The amount of charge flowing past a given point every second
Formula for charge, current and time
Q
I. T
IQT- I cutie
What is 1 mega amp in amps
0.001 AMPS
What is charge and current measure in
Charge- amps
Current- coulombs
What is potential difference
Pd tells you how many coulombs of charge is transferred from a battery to a component in a circuit
⭐️How much energy can be given to the bulb from the battery
What’s the equation for current resistance and potential difference
V
I. R
IVR
What two values are inversely proportional and what two values are directly proportional
Proportional- PD and current
Inversed- current and resistance
What is resistance
Anything that can reduce flow of current in a circuit
Is a voltmeter connected in series or in parallel
In parallel
What is ohms law
The current through a component is proportional to the PD across it provided that its temperature remains constant
On an I-V graph for a filament bulb, at first the line will appears steep then it spread out move evenly as it goes up .
Why is this the case?
This is because when the filament first turns on it is cold. This means there’s less resistance due to less electric charge flowing through . This makes the first part steep
When the filament in the bulb starts to heat up there is more resistance caused by the electric charge. This means the graph starts to spread out and become less steep.
What happens when the temperature increases in a thermistor
What happens when the light intensity increases in an LDR
When the temperature increases the resistance decreases
When the light intensity increases the resistance decreases
What is a diode
A component that only allows a current to flow in one direction- from the positive end of the battery to the negative end
What happens when you turn a diode to reverse direction?
No current will flow through. This is why on the IV graph for diodes there is a flat line on the negative (reverse side) of the graph
What is the difference between direct and alternating current
Direct- current goes one direction only
Alternating- the direction of current changes
What’s the difference between potential difference in series and parallel circuits
Series/ TOTAL PD OF POWER SUPPLY IS SHARED BETWEEN COMPONENTS
Branch1:3V
branch2:6V
parallel/PD ACROSS EACH BRANCH IS THE SAME AS EACHOTHER
branch1:9V
Branch2:9V
What’s the difference between resistance in series and parallel circuits
Series- total resistance is sum of resistances of each component
Parallel- total resistance is less than the resistance of each resistor
In a parallel circuit the total resistance is lower than the resistance of both resistors. Why does the resistance decrease?
A parallel circuit provides two pathways for the current instead of one
This means the current is more evenly spread out which makes it easier for current to flow through
The overall resistance has decreased
INVESTIGATING RESISTANCE IN CIRCUITS
what is the control variable
Type of wire
diameter of wire
temperature of wire-temperature
INVESTIGATING RESISTANCE IN CIRCUITS
How to answer to. ”suggest a possible reason for anomalous result”
⭐️The student read the reading on the ammeter wrong-example
This response can be anything simple that makes sense, don’t over complicate
What are the three equations for power
PET
PIV
PI^2R
What does I represent in an equation
Currrnt in amps
