Transcript (A) Resistance - Noadswood Science

Additional Physics – Forces
Exam Date -
“Resistance is
futile!”
L/O :- To know what affects the
resistance in a circuit
Quick quiz
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What is the equation for work done?
What affects your momentum?
How do you work out speed?
What 2 equations can you use to work out acceleration?
What is acceleration measured in?
What is the equation for work done and what is it
measured in?
• What is Hooke’s law?
• What is the equation for working out current?
• Name 3 things which can affect stopping distance
1
Can you remember
what these symbols
mean?
2
3
4
5
6
7
8
Heater
Fuse
Motor
Transformer
LED (light emitting diode)
Diode
Lamp
Generator
Resistance
Electrons passing through a bulb have to push their
way through lots of vibrating ions in the metal
filament. The ions resist the passage of electrons
through the bulb
Resistance = Potential difference (volts)
(ohms)
Current (amperes)
What is electrical
resistance?
What do you think
affects the resistance
of a wire?
Write a hypothesis to investigate?
What affects the resistance of a wire?
Hypothesis
Prediction
Independent variable =
Dependent variable =
Method
Equipment
Gather your results and graph these. You will be
expected to tell the class what patterns you found in
your results at the end of the lesson
Voltage
(V)
Current
(A)
Resistance
(Ω)
Resistance (Ω)
Independent
Independent Variable
Do your results support
your prediction?
What do the results of the
rest of the class tell you
about what affects the
resistance of a wire?
Do your results follow
ohm’s law?
Ohm’s Law
The current through a resistor at constant
temperature is directly proportional to the potential
difference across the resistor
If not, why not?
What have you learnt?
• Do you know the equation for
resistance?
• Can you explain what resistance
is?
• Do you know what affects
resistance?