Go to Main SiteMobile Site IndexMobile Site Index
 
Answer

Answers to Potential Difference Questions

A1. The 'slope' has doubled in steepness, so the charges will flow more rapidly - the current will

double: 0.50 A

 

A2. If the current flowing is only a third of that before... the 'slope' must also only be a third of the value: 1V
 

Answers to Potential Division Questions

A1.  First we have to find out how many ohms have to share out the 'potential drop' (the voltage).

 6V is shared by 1200W.

Therefore each 100W gets 0.5V and the 700W gets 0.5 x 7 = 3.5V

A2.   5V is shared by 2000W.

Therefore each 100W gets 0.25V and the 700W gets 7 x 0.25 = 1.75V

A3.   This question is at GCSE high attainment level or AS level..... so don't worry about it at KS3!

The first step is to convert the parallel arrangements into single resistors.

Those that are the same as each other are easy and can be done by inspection:

       so we have       

The dissimilar ones have to be tackled using the equation for resistors in parallel

so we have   

This gives us a newly drawn circuit in a form in which  we can share potential drop easily

10V is shared by 1005W.

Therefore each 1W gets 0.00995V and the 300W gets 2.98V (which you would round off to 3.0V as the values are to 2 significant figures).

'Croc Clips' allows us to test this......

Why not try a few circuits of your own to test your ability to analyse them?

Go to Main Site
Mobile Site Index