HDE Section 3: Electric Circuits

Question 1

What is charge?

Answer 1

Charge is a property that particles or objects can have.
The charge of a particle or object can be described as positive (+), negative (-), or neutral.
Charge is measured in coulombs (C).

Question 2

Describe the structure of a metal

Answer 2

Within a metal there is a regular structure of positive ions, with a sea of delocalised electrons moving in between.

Question 3

Define Current

Answer 3

the rate of flow of charge.

Question 4

Conventional current flows from _____ to _______: in a current made of electrons, the actual electrons are flowing in the ________ direction to the conventional current.

Answer 4

Conventional current flows from positive to negative: in a current made of electrons, the actual electrons are flowing in the opposite direction to the conventional current.

Question 5

Explain why the reading on the ammeter changes when the switch is opened and closed.

Answer 5

Mark Scheme
State what the ammeter measures.
Describe the motion of the electrons when the switch it open.
Describe the motion of the electrons when the switch it closed.
State the definition for current.
State what the battery supplies to the circuit.
Describe how opposite charges interact.

Question 6

Convert to base units:
200 mA
350 mA
5 kV
4 mins
120 kW
2.6 hours

Answer 6

0.2 A
0.35 A
5000 V
240 s
120, 000 W
9360 s

Question 7

Take a 5-minute break and rate this card 5

Answer 7

Take a 5-minute break and rate this card 5

Question 8

How much charge flows through the filament of an electric lamp in 1 hour when the current in it is 250 mA?

The electron charge is 1.6 x 10^-19C. How many electrons flow through the filament during this time?

Answer 8

900C

5.6 x 10^21