Resistance Flashcards
A material with many free electrons will pass current freely is called ?
A conductor
Name some examples of a conductor
Platinum
Impure water
Gold
Aluminium
Copper
Mercury
Carbon
Sliver
Brass
What is a material with few free electrons and will only pass current with difficulty is called ?
An insulator
Name examples of insulators
Porcelain
Paper
Glass
Plastic
Rubber
Mica
Wood
Insulating varnish
Woven fabrics
What different factors affect the resistance of a conductor?
Length of conductor
Type of a material
Temperature
Cross sectional area of conductor
What does ohms law state ?
That current flowing through a conductor is directly proportional to the applied voltage and inversely proportional to the resistance
What is in Ohms law triangle?
Voltage (V = I x R)
Current (I = V / R)
Resistance (R = V / I)
What must remain constant, for Ohms Law to be true ?
Temperature
What is the unit of resistance?
Ohms
State the formula for calculating total resistance in a series circuit
Rt=R1+R2+R3
What should show that the answer of total resistance in a parallel circuit is the correct answer?
Rt should have a lower valve than the lowest resistor
State the formula for calculating total resistance in a parallel circuit
1/Rt = 1/R1 + 2/R2 + 3/R3