Dynamic electricity Flashcards
(17 cards)
what is dynamic electricity?
The steady flow of electrons between objects or places. It comes from far away on wires
Does dynamic electricity need a conductor? A circuit?
Yes. It needs a substance that allows electrons to move easily through it
Yes, a closed circuit is needed to flow
What direction does current flow? How is this drawn?
From - to +
From small line to bigger line
What is current? Why does it happen?
A flow of electrons.
Only valence electrons can move and are passed from one atom to the next because same charges repel
Define current intensity
(I) the speed of movement of electrical charges in a circuit
Measured in Amps (A)
What is the formula for Current Intensity?
A=c/s
Current intensity (a)= Coulombs (C)/Seconds (s)
What factors change the current intensity?
- Thickness of wire high diameter, high I - Resistance high R, low I - Length of wire very long, low I - Temperature high temp., low I - Nature of wire high I, high conductance
Define resistance
The ability of a material to hinder (slow/stop) the flow of electrical current.
Is energy lost when using resistors?
The energy of electrons flow will be lost as heat
Define potential difference
The amount of force on electrical charges in a circuit (V)
What is the formula for potential difference?
V=E/q
potential difference (V)= energy transferred (Joule)/the charge (C)
What is Ohms law?
V=IR
Potential difference (V)= Current intensity (A) x Resistance (ohms)
Where are ammeters placed?
in the path a charge will take
connected in series
Where are voltmeters placed?
At the points where a circuit enters and exits a component
connected in parallel
it measures potential difference across a component
Current and potential difference have what kind of relationship?
What is this called?
Directly proportional?
Ohm’s law
Look at graphs on the back of “Dynamic electricity package”
study
Study static electricity
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