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History of the Atom
Ions
Electric Current
Electric Circuits
Grab Bag
100
Who was the ancient Greek philosopher that coined the phrase "the Atom"?
Democritus
100
What is an ion?
An atom that has a charge; cations and anions
100
What is an insulator?
Materials that do not allow electrons to move from place to place easily.
100
What are the requirements of an electric circuit?
- closed loop - energy source -can have devices.
100
What is the atomic number tell us about an atom?
the number of protons in the nucleus
200
Who created the solid sphere model of the atom?
John Dalton
200
How do ions move in a solid?
Electrons can move from atom to atom
200
What is a conductor?
Materials that electrons can move easily from place to place.
200
Why must the circuit be a closed loop?
it must have a continuous flow of electric charge.
200
What is the mass number of an atom?
Tells us the number of protons and neutrons in an atom
300
Who conducted an experiment using a cathode ray tube and discovered electrons?
J J Thomson
300
How do ions move in a solution?
The whole ion can move, not just passing electrons.
300
What is electric current?
Flow of electric charges. Measures the number of electrons passing though a given point. Units = amps.
300
What is resistance?
A measure of how difficult it is for electrons to flow through a material. Units = Ohms
300
What is an isotope
Atoms of the same element that have a different number of neutrons.
400
Who conducted an experiment in which alpha particles were shot at gold foil and discovered the nucleus?
Ernest Rutherford
400
Explain attractive and repulsive forces in terms of negative and positive.
negative-negative and positive-positive are repulsive negative-positive are attractive
400
What is voltage?
the measure of how much electrical potential energy an electron can gain. In other words, its the "push" available to the electrons. Units = Volts
400
What is Ohm's law?
V = I x R v = volts I = current in amps R - resistance in ohms
400
What is the difference between series and parallel circuits?
Series circuit only has one path for electric current to flow while parallel circuits have more than one path for current to flow.
500
According to the modern day model of the atom, where are electrons found?
in the electron cloud.
500
What is the difference between electric field and electric force?
Electric force is the attractive or repulsive force that an ion can apply while electric field is the force that is exerted from a certain distance.
500
What are watts?
Unit of power for electricity. It tells the rate of how much work a circuit can perform.
500
How do length and thickness of wire impact resistance?
Resistance increases as wire becomes thin or more narrow. Resistance increases as wire becomes longer.
500
Why is it incorrect to say batteries need "recharged"?
Batteries don't provide a charge, they provide energy.