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WorksheetsI-V Characteristics
Total questions: 17
Worksheet time: 8mins
The graph shows the change in current with potential difference for
an LED
a filament lamp
a diode
a thermistor
To calculate the resistance of the component at a particular potential difference you
read the current at that point on the graph and calculate p.d divided by current
draw a tangent to the line at that point and calculate the gradient
draw a tangent to the line at that point and calculate 1/gradient
read the current at that point on the graph and calculate current/p.d
The resistance of the component
is always constant as the p.d. increases
starts high and then decreases as the p.d. increases
starts constant for low values of p.d. and then increases as the p.d. increases
starts constant for low values of p.d. and then decreases as the p.d. increases
Which component has the highest resistance?
1
2
The components 1 and 2 which produced this IV graph are:
Resistors
Filament lamps
Diodes
A combination of the above
Where would you place an ammeter in the circuit?
Green ?
Red ?
Where would you place a voltmeter in the circuit?
Green ?
Red ?
What is the unit of measurement for resistance?
Voltage
Ampere
Watts
Ohms
the formula to find current when the values of V and R are known is
I = V2R
I = V/R
I = R/V
I=VR
which component produces an IV graph like this?
resistor
diode
filament bulb
fuse
which component produces an IV graph like this?
resistor
diode
filament bulb
fuse
What relationship is shown by this graph (choose two true statements)
A linear relationship
A directly proportional relationship
A non-linear relationship
An inverse relationship
The diagram shows the circuit used to obtain the data needed to plot the current-potential difference graph for a filament lamp.
Why is component M included in the circuit?
To keep the current constant.
To keep the potential difference constant.
To vary the current.
To vary the bulbs resistance.
What happens to the resistance of a filament lamp as the potential difference increases? Why?
It is constant. The resistance of a filament lamp always remains the same.
It decreases. As the potential difference increases, more electrons are pushed through the wire in the lamp in a smaller time and so the resistance decreases.
It increases. As the potential difference increases, the current also increases which heats the filament making it harder for electrons to flow.
What happens to the resistance of a fixed resistor as the potential difference increases?
It remains constant
It increases
It decreases
Which best describes the resistance of a diode
The resistance increases as the potential difference increases
The resistance is extremely big when the potential difference is negative and becomes smaller after a small positive potential difference
The resistance is nothing when the potential difference is negative and increases when the potential difference increases
When current flows negatively the resistance is infinite and when it flows positively the resistance decreases
