A-LEVEL Physics: 5.1.1: Basics of Electricity (SaveMyExams)

Question 1

simple electrical circuit requires: (2)

Answer 1

-conductor (so current can flow)

-source of potential difference

Question 2

current:

Answer 2

rate of flow of charge
net flow of electrons

Question 3

current = …

Answer 3

charge / time

I=∆Q/∆t

Question 4

current flows when a ___ is formed. when is this?

Answer 4

circuit.
when a conductor (eg wire) connects 2 oppositely charged terminals of a source (eg cell)

Question 5

conventional current:

Answer 5

net flow of charge from positive terminal of a cell to negative terminal

Question 6

ammeters must be connected in ___ with the component to measure its current. why?

Answer 6

series
current in = for components in series

Question 7

potential difference:

Answer 7

electrical work done per unit charge between 2 points
energy transferred per unit charge

Question 8

potential difference =

Answer 8

energy transferred / charge

V=E/Q

Question 9

how does a simple cell create a potential difference?

Answer 9

2 oppositely charged terminals: positive & negative

Question 10

voltmeters must be connected in ___ with the component being measured

Answer 10

parallel

Question 11

resistance:

Answer 11

opposition of a component to the flow of current through it

Question 12

resistance =

Answer 12

voltage / current

R=V/I

Question 13

resistance of a component controls the size of the ___ in the series circuit

Answer 13

current

Question 14

resistance & current are ___ proportional

Answer 14

inversely

Question 15

why are wires often made of copper?

Answer 15

low electrical resistance, good conductor