Electricity Flashcards
(26 cards)
What is the unit of electric current?
Ampere (A)
True or False: Voltage is the measure of electric potential difference.
True
Fill in the blank: The resistance of a conductor is directly proportional to its length and inversely proportional to its _______.
cross-sectional area
What is Ohm’s Law?
V = IR, where V is voltage, I is current, and R is resistance.
What is the formula for calculating electrical power?
P = IV, where P is power, I is current, and V is voltage.
What is the SI unit of capacitance?
Farad (F)
True or False: A series circuit has the same current flowing through all components.
True
What does a capacitor do?
Stores electrical energy in an electric field.
Fill in the blank: The total resistance in a series circuit is the _______ of the individual resistances.
sum
What is Kirchhoff’s Voltage Law?
The sum of the electrical potential differences (voltage) around any closed network is zero.
What is the relationship between current, voltage, and resistance in a parallel circuit?
Voltage is the same across all components, while the total current is the sum of the currents through each component.
What is the purpose of a fuse in an electrical circuit?
To protect the circuit by breaking the connection when current exceeds a certain level.
True or False: In a parallel circuit, if one component fails, the current can still flow through other components.
True
What is the unit of electric energy?
Joule (J)
What does the term ‘electromotive force’ (EMF) refer to?
The energy provided per coulomb of charge by a source.
Fill in the blank: The power dissipated in a resistor can also be calculated using the formula P = R _______.
I^2
What is the role of a transformer?
To change the voltage level in an AC circuit.
What is the difference between direct current (DC) and alternating current (AC)?
DC flows in one direction, while AC changes direction periodically.
True or False: Superconductors have zero resistance below a certain temperature.
True
What is the principle of conservation of charge?
The total electric charge in an isolated system remains constant.
What is a diode?
A semiconductor device that allows current to flow in one direction only.
Fill in the blank: The total capacitance of capacitors in series is always _______ than the smallest capacitor.
less
What is the effect of temperature on the resistance of conductors?
Resistance typically increases with temperature.
What is the purpose of a battery in a circuit?
To provide a source of electrical energy.
