Basics of Electricity and Basic Laws

A 3.3 kΩ resistor dissipates 0.25 W. The current is

• 8.7mA

• 87mA

• 8.7µA

• 8.7A

Answer explanation

Using P = I^2 * R, we can find I = sqrt(P/R) = sqrt(0.25/3300) = 0.0087A = 8.7mA. Therefore, the correct answer is 8.7mA.

A 4.7 kΩ resistor dissipates 0.5 W. The current is

• 106.38mA

• 10.63mA

• 1.06mA

• 106.3µA

Answer explanation

Using the formula P = I^2 * R, we can find the current I = sqrt(P / R). Substituting the values, I = sqrt(0.5 / 4700) = 0.01063 A = 10.63mA.

If a 2.2 kΩ resistor has a current of 15mA passing through it, what is the power dissipated?

• 495 mW

• 22 mW

• 495 W

• 2 W

Answer explanation

To calculate power, use the formula P = I^2 * R.

Calculate the resistance if a 12V battery is connected to a circuit with a current of 2A flowing through it.

• 6 Ω

• 10 Ω

• 24 Ω

• 8 Ω

Answer explanation

Using Ohm's Law (V = IR), resistance (R) = V/I = 12V/2A = 6 Ω

If a 5.6 kΩ resistor dissipates 0.75 W, what is the current flowing through it?

• 115.73 nA

• 1.157 A

• 11.57 mA

• 11.57 µA

Answer explanation

Using P = I^2 * R, we can find I = sqrt(P / R).

What is the power dissipated by a 1.8 kΩ resistor with a current of 20mA passing through it?

• 0.72 W

• 0.36 W

• 0.18 W

• 0.02 W

Answer explanation

The power dissipated by a resistor can be calculated using the formula P = I^2 * R.

If a 9V battery is connected to a circuit with a resistance of 450Ω, what is the current flowing through the circuit?

• 20mA

• 2mA

• 0.02A

• 0.2A

Answer explanation

Using Ohm's Law (V=IR), current (I) = Voltage (V) / Resistance (R).

Voltage is the product of ---------------- and -----------------  

• Energy and charge

• Resistance and Current

• Current and Temperature

• Resistance and Temperature

Answer explanation

Voltage is the product of Resistance and Current, as stated in the question. Therefore, the correct choice is Resistance and Current.

What is the power dissipated by a 3.9 kΩ resistor with a current of 25mA passing through it?

• 0.97 W

• 2.44 W

• 0.25 W

• 0.09 W

Answer explanation

The power dissipated by a resistor can be calculated using the formula P = I^2 * R, where I is the current and R is the resistance. Substituting the values, we get P = (0.025)^2 * 3900 = 2.4375 W.

If a 6V battery is connected to a circuit with a resistance of 300Ω, what is the current flowing through the circuit?

• 2 mA

• 20 mA

• 0.2 A

• 2 A

Answer explanation

To calculate current, use Ohm's Law: I = V / R. Given V = 6V and R = 300Ω, I = 6V / 300Ω = 0.2A.