Electricity and magnetism: Flashcards
Which atoms can be transferred?
Electrons
What charge do neutrons have?
Neutral
What charge do protons have?
Positive
What charge do electrons have?
Negative
Where are electrons located in the nucleus?
they surround the nucleus
Where are protons/neutrons located in the nucleus?
The outside
When two electrons with the same charge are close what happens?
They repel
When electrons with different charges are close what happens?
They attract
What tells you the number of electrons and protons in an atom?
The big number in an atom on the periodic table
How do you tell the number of neutrons and protons in an atom?
The big number - the small number
What does the group in the periodic table tell us?
how many electrons on the outer shell
What is potential difference?
The size of the push of the battery
What do you call 2 or more cells joined together?
A battery
What are 3 factors that affect resistance:
Temperature
Length of wire
thickness of wire
What is resistance?
A measure of how difficult it is for current to flow
What is the formula to calculate resistance?
Resistance ( R ) = potential difference ( V )/current ( L )
What three elements are attracted to magnets?
Iron, cobalt and nickel
What do North poles attract?
South poles
What do North poles repel?
North poles
What do South poles attract?
North poles
What do South poles repel?
South poles
Do long or short wires have higher resistance?
Long
What is current?
The rate of flow of charge
How is a battery different to a cell?
A battery contains electrical energy which is presupplied from a factory, while cells contain a chemical energy source such as natural gas
How is an electromagnet made?
By wrapping a wire around an electric core
What affects the strength of electromagnets?
Current
Number of coils
type of magnetic core
What is potential difference?
The energy transferred per unit charge as charges flow between two points on a circuit
What is current?
The rate of flow of charge
What is charge caused by?
Atoms losing or gaining electrons
How do you calculate current?
Current ( L ) = potential difference ( V )/resistance ( R )
How do you calculate potential difference?
Potential difference ( V ) = Current ( L ) x Resistance ( R )
What is energy?
The potential to do work
What is the formula for energy?
Work force x distance
