Resistance Flashcards
A material with many free electrons will pass current freely is called a ?
Conductor
What are examples of conductors
Copper Brass Silver Carbon Impure water (salt water) Aluminium Platinum Mercury Gold
What is a material with few free electrons,and will only pass current with diffuculty
An insulator
What are examples of insulators
Glass Wood Paper Rubber Mica Insulating varnish Porceleain Plastic Woven fabrics
What are the diffrent factors inwhich affects the resistance of a conductor
Length of conductor
Type of material
Temperature
Ohm’s law states that a_____flowing through a conductor…
Current
…is directly proportional to the applied _______ across it
Voltage
…providing the_____ remains constant
Temperature
And is _____ proportinal to the resistance.
Inversley
What is the unit of resistance
Ohms
State the formula for calculating toral resistance in a parellel circuit
1/Rt = 1/R1 + 1/R2 + 1/R3
After working out total resistance (Rt) in a parallel circuit , what is a good check that your answer is correct
Rt should have a lower value than the lowest resistor