Week 3 Quiz: Electrostatics and Current

What are the requirements for current to flow in a circuit?

• A path for the current to flow along

• Charge carriers (charged particles) that are free to move

• A force applied to make them start moving

• An alternating wave

List the electronic devices shown in the circuit diagram below.

• Ammeter

• Load

• Switch

• Resistor

• Battery

Answer explanation

That's not a battery, it's a cell.

Why do scientists refer to conventional current as flowing from positive to negative?

• Protons flow from the positive terminal of a battery to a negative terminal

• Electrons flow from the positive terminal of a battery to the negative terminal of the battery.

• Originally, scientists thought charge carriers were positive

• Charges flow in both directions in a wire; a conventional current refers to just one flow

Answer explanation

Protons flow option; protons don't flow

Electrons flow option; electrons flow from negative to positive

Originally option; correct

Charges flow in both directions; protons can't flow, charge will only flow in one direction

A charge of 30C flows through copper wire.

What current flows through the wire in 10 seconds?

A charge of 30C flows through copper wire.

What current flows through the wire in 1 minute?

A charge of 30C flows through copper wire.

What current flows through the wire in 1 hour?

(Write your answer to two significant figures, don't put any spaces)

A headlight may draw a current of 5A. How much charge will have flowed through it in 1 second

Answer explanation

Don't forget units.

A headlight may draw a current of 5A. How much charge will have flowed through it in 1 minute?

Answer explanation

Don't forget units.

A headlight may draw a current of 5A. How much charge will have flowed through it in 1 hour?

Answer explanation

Don't forget units.

Using the table, find how much charge a pocket calculator generates in 10 minutes.

Answer in SI units.