Nov Test Flashcards
State Ohm’s law
The current through a resistor is directly proportional to the potential difference across it as long as the temperature remains constant
When a current lights a bulb, what is flowing in the wires?
Electrons
Define current
The flow of electric charge
What would happen with a higher voltage?
More energy per electron is being delivered to the components
What would happen if you increase the number of cells in a series circuit?
It will increase the brightness of the bulbs because the electrons are giving more energy
What is an electric current and what is it measured in?
The rate of flow of charge
Amps
In electric circuits electrons flow. Are they positive or negative?
Negative
With an electrostatic car paint sprayer, paint leaving the gun is made positive. What charge should the car have?
Negative so the paint is attracted to it
Why should electrostatic paint spraying be done in a dust-free environment?
So the paint doesn’t get attracted to the dust
Why in a electrostatic paint sprayer does the paint not stick together?
Because the paint is positive so all repels and spreads out in a ‘fine mist’
How does a dust precipitator work?
It removes particles from a gas stream by using electrical energy to charge particles either positively or negatively so will attract to the side plates
How in a dust precipitator could you get dust off the side plates?
Uncharge them (make them neutral) so they don’t attract or repel and fall off
What two ways can an object become charged?
Friction and induction
What charges attract and repel
Like charges repel
Opposite charges attract
Why are charges evenly distributed in a conductor?
As they all repel each other and move away so they spread out
