Electricity: Electric Charge Flashcards
What is an electrical conductor?
A material in which current flows through easily.
Name some good conductors.
Metals, graphite, salt solutions or molten salts.
What is an electrical insulator?
Electrical insulators have a high resistance to the flow of electric current.
Give some examples of insulators.
Plastic, dry wood, glass and rubber.
Gold and silver are better conductors than copper, so why is copper used in wires?
Copper is used in pipes because it is a very good conductor of electricity and fairly inexpensive in comparison to silver and gold.
What is a series circuit?
One in which all the components are connects end to end.
How do you calculate current in a series circuit?
It is the same everywhere so place an ammeter anywhere.
How is the voltage dispersed across a series circuit?
The voltage splits up so that the sum of the voltage across the individual components is equal to the voltage of the power supply or battery.
What is a parallel circuit?
A circuit in which all the components are connected side by side.
How is the voltage dispersed across a parallel circuit?
The voltage is the same across each branch.
How is the current dispersed across a parallel circuit?
The current splits up so that the sum of the currents in each branch will add up to the current supplied by the battery or power supply.
Which circuits are Christmas tree lights connected in? Why?
Series so that small, low voltage bulbs can be used. However this means that if one bulb breaks the whole thing stops working.
Which circuits are the lights in your home? Why?
Parallel so each bulb can be switched on and off separately and the brightness of one bulb does not change whether some bulbs are on or off. Also if one bulb breaks or is removed you can still use the other ones.
What is current?
The rate of a flow of charge.
What is the relationship between charge, current and time?
Charge = current*time Q = I*t
