Grade 8 Science Flashcards
What is Ohm’s law?
Ohm’s law states that the current through a conductor between two points is directly proportional to the voltage across the two points.
What is the formula for Ohm’s law?
The formula for Ohm’s law is V = I * R, where V is the voltage, I is the current, and R is the resistance.
What is the unit of resistance?
The unit of resistance is the ohm, symbolized by the Greek letter omega (Ω).
True or False: Resistance is the opposition to the flow of electric current.
True
What happens to current if resistance increases in a circuit?
If resistance increases in a circuit, the current decreases.
Fill in the blank: According to Ohm’s law, current is proportional to ________.
voltage
What is the relationship between voltage and current in a circuit according to Ohm’s law?
Voltage and current are directly proportional in a circuit according to Ohm’s law.
If the voltage in a circuit is 12 volts and the resistance is 4 ohms, what is the current flowing through the circuit?
The current flowing through the circuit is 3 amperes.
What is the SI unit of current?
The SI unit of current is the ampere.
What is the relationship between resistance and current in a circuit according to Ohm’s law?
Resistance and current are inversely proportional in a circuit according to Ohm’s law.
What happens to current if voltage increases in a circuit?
If voltage increases in a circuit, the current also increases.
What is the formula for calculating resistance using Ohm’s law?
The formula for calculating resistance using Ohm’s law is R = V / I, where R is the resistance, V is the voltage, and I is the current.
Fill in the blank: According to Ohm’s law, resistance is inversely proportional to ________.
current
What is the relationship between voltage and resistance in a circuit according to Ohm’s law?
Voltage and resistance are directly proportional in a circuit according to Ohm’s law.
If the current in a circuit is 5 amperes and the resistance is 10 ohms, what is the voltage across the circuit?
The voltage across the circuit is 50 volts.
True or False: Ohm’s law is only applicable to resistive circuits.
False
What is the relationship between power, current, and voltage in a circuit?
The relationship between power, current, and voltage in a circuit is given by the formula P = V * I, where P is power, V is voltage, and I is current.
What is the formula for calculating power in a circuit?
The formula for calculating power in a circuit is P = V * I, where P is power, V is voltage, and I is current.
What is the SI unit of power?
The SI unit of power is the watt.
If the voltage in a circuit is 24 volts and the current is 6 amperes, what is the power consumed by the circuit?
The power consumed by the circuit is 144 watts.
Fill in the blank: Power is the rate at which ________ is done in a circuit.
work
True or False: Power dissipation in a circuit is independent of resistance.
False
What is the formula for calculating power dissipation in a circuit with resistance?
The formula for calculating power dissipation in a circuit with resistance is P = I^2 * R, where P is power, I is current, and R is resistance.
If the current in a circuit is 2 amperes and the resistance is 5 ohms, what is the power dissipation in the circuit?
The power dissipation in the circuit is 20 watts.
