Exploring Electric Current and Circuits

What does conventional current imply about the direction of flow of charge?

• Random direction

• From lower to higher potential

• From positive to negative terminal

• From negative to positive terminal

What happens to the current if the voltage is increased while resistance is constant?

• It decreases

• It remains constant

• It increases

• It becomes zero

Which formula represents the power as a function of resistance and current?

• P = V/I

• P = VI

• P = I^2R

• P = V^2/R

How do you calculate the number of electrons passing a point in a circuit if the charge is known?

• Add the electron charge to the total charge

• Divide the charge by the electron charge

• Multiply the charge by the electron charge

• Subtract the electron charge from the total charge

What is the resistance of a light bulb if it is connected to a 12V battery and draws 150mA of current?

• 120 ohms

• 60 ohms

• 80 ohms

• 100 ohms

How much power does a resistor consume if it has a resistance of 250 ohms and a current of 0.036 amps flows through it?

• 0.5 watts

• 0.324 watts

• 1 watt

• 2 watts

What is the voltage across a motor that uses 50 watts of power and draws a current of 400 milliamps?

• 150 volts

• 100 volts

• 125 volts

• 200 volts

If a resistor has a resistance of 5 kilo-ohms and a current of 0.026 amps, what is the power consumed?

• 3.38 watts

• 5 watts

• 10 watts

• 1 watt

What is the internal resistance of a motor if it operates at 125 volts and draws a current of 0.4 amps?

• 100 ohms

• 312.5 ohms

• 150 ohms

• 200 ohms

How much energy does a light bulb consume over a month if it operates at 1.8 watts and electricity costs 11 cents per kilowatt-hour?

• 10 cents

• 14 cents

• 5 cents

• 20 cents