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Resistance: it's not Futile
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Electrical Resistance: the ability of a material to
oppose the flow of electric current
-measured in Ohms (Ω)
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Electrical Resistance: the ability of a material to
oppose the flow of electric current
-measured in Ohms (Ω)
Factors affecting Resistance:
1. type of material
e.g. silver is a better conductor than copper
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Electrical Resistance: the ability of a material to
oppose the flow of electric current
-measured in Ohms (Ω)
Factors affecting Resistance:
1. type of material
e.g. silver is a better conductor than copper
2. cross-sectional area
-thicker wires have less resistance
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Electrical Resistance: the ability of a material to
oppose the flow of electric current
-measured in Ohms (Ω)
Factors affecting Resistance:
1. type of material
e.g. silver is a better conductor than copper
2. cross-sectional area
-thicker wires have less resistance
3. length
-longer wires have more resistance
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Electrical Resistance: the ability of a material to
oppose the flow of electric current
-measured in Ohms (Ω)
Factors affecting Resistance:
1. type of material
e.g. silver is a better conductor than copper
2. cross-sectional area
-thicker wires have less resistance
3. length
-longer wires have more resistance
4. temperature
-resistance increases with temperature
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Resistor: a device that reduces the flow of electric
current
-all loads provide resistance but resistors are
sometimes added to reduce the current flow to
specific areas of the circuit
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Resistor: a device that reduces the flow of electric
current
-all loads provide resistance but resistors are
sometimes added to reduce the current flow to
specific areas of the circuit
Short Circuit: a circuit without a load offers no
resistance.
-more & more electrons flow through the wire
until it overheats and melts or catches on fire.
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Measuring Resistance: an ohmmeter is
connected in parallel with a resistor
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
Ohm's Law: the straight line relationship between
voltage and current
R=V
I
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
e.g. A load has 1.2 A of current flowing through it.
The voltage across the load is 6.0 V. Calculate the
resistance of the load.
LG: to relate current & potential difference through resistance
Resistance: it's not Futile
e.g. A load has 1.2 A of current flowing through it.
The voltage across the load is 6.0 V. Calculate the
resistance of the load.
Given: current (I) = 1.2 A
potential difference (V) = 6.0 V
Unknown: resistance (R)
Select: R=V
I
Solution: R = 6.0
1.2
= 5.0 Ω
LG: to relate current & potential difference through resistance