All Flashcards
What is the effect of increasing the length of a wire on its resistance?
Increasing the length increases the resistance.
What is the effect of increasing the cross-sectional area of a wire on its resistance?
Increasing the cross-sectional area decreases the resistance.
What happens to the current in a circuit if the voltage is doubled, assuming resistance remains constant?
The current doubles (Ohm's Law: V=IR).
What happens to the total resistance when resistors are added in series?
The total resistance increases.
What happens to the total resistance when resistors are added in parallel?
The total resistance decreases.
What is the effect of increasing temperature on the resistivity of most materials?
Increasing temperature typically increases resistivity.
Define electric current (I).
The rate of charge flow, measured in Amperes (A). I = dQ/dt
Define drift velocity (v_d).
The average velocity of charge carriers (e.g., electrons) due to an electric field.
Define current density (J).
A vector quantity that relates current to the electric field and material properties. J = I/A = σE
Define resistance (R).
The opposition to current flow in a circuit, measured in Ohms (Ω).
Define resistivity (ρ).
A material property that describes how much it resists current flow.
Define electric power (P).
The rate at which electrical energy is used, measured in Watts (W). P = IV
In a simple circuit diagram, what symbol represents a resistor?
A zig-zag line: ~~~
In a simple circuit diagram, what symbol represents a battery?
A long and short parallel line: -| |-
What is the symbol for a capacitor?
Two parallel lines of equal length: | |
What is the symbol for an inductor?
A coiled line: ⌁⌁⌁
What is the symbol for a closed switch?
A line with a hinged connector making contact: - / -