Electric Current Flashcards
What is an atom made up of?
Charged particles: positive nucleus with negative electrons orbiting it: nucleus made up of neutral neurone and positive protons.
Where are there electrostatic forces?
Between charged objects: hair stands up when it is attracted to a charged comb.
There is a … between the positively charged nucleus and the negatively charged electrons in an atom:
Electrostatic force of attraction.
How can the outermost electrons be removed?
By rubbing as they’re less strongly attracted to the nucleus.
What happens when two insulating objects are rubbed together?
They become charged: electrons are transferred from one object to the other: object has lost electrons become positively charged: object has gained electrons will become negatively charged.
What makes your hair stand up?
The individual hairs similarly charged and repel each other.
Why can there be a spark or crackle when a nylon or polyester top is taken off?
Caused by the electrons moving through the air from the negatively charged clothing to your positively charged hair.
Why are metals good conductors?
They have free electrons: lots of charges free to move.
Why are plastics electrical insulators?
There are few free elections in plastics so there are few charges free to move.
What is an electric current?
When the bulb is lit in a circuit.
What is there in a complete circuit?
Free electrons in all the metal components and connecting wires: cell supplies energy to the electrons: electrons carry a negative charge so they will flow from the negative terminal of the cell towards the positive terminal.
What is the bulb converting the energy to?
The energy carried by electrons into light and heat energy.
What is the rate of flow of charge?
The electric current or the charge flowing per second.
What makes the current greater?
The more energy the charged particles receive from the power supply.
What happens in an electric circuit?
The charge is conserved and energy is transferred.
