# solutions to higher physics unit 2 practice NAB

Sorry folks, the link I put up here earlier did not have the answers to the practice NAB for unit 2 of Higher Physics.  I’ve written my answers for you instead, with mark allocation indicated down the side in red.

### 2 thoughts on “solutions to higher physics unit 2 practice NAB”

1. Calum

For the first answer, it says E=QV, when the databook states E=1/2QV. Is this just a mistake on the answers?

• mrmackenzie

Oops! You’re mixing up the relationships for capacitors with those for charged particles in an electric field. If there is a 1/2 in the equation, it’s a capacitor equation. The 1/2 part comes from a unit 2 experiment where energy stored by the capacitor is found to equal the area under a graph of charge vs voltage, hence E = 1/2 x base x height = 1/2 x Q x V.

In the SQA blue booklet, the capacitor equations are all in a row.

SQA use W=QV for Work Done on the charge by the electric field but in the Int2/Standard Grade section, Ew is used to represent work done (as in Ew=Fd). E=QV is another way of writing this same relationship. Check your notes and see which way your teacher showed it. It will be at the very start of your unit 2 work.