Help!!

Hello!!
''The diagram shows how the electric potential varies along a line XX' in an electric field. What will be the electric field strength at a point P on XX' which is mid-way between R and S?''

I've been really stuck on this question and would really appreciate any help anyone could possibly give!!

Thank you all!!

Physics Question.JPG14.6KB

Reply 1

phys981

From your diagam, the potential is varying linearly, so the potential midway between R and S will just be halfway between 20 and 30V, ie 25 V

Reply 2

anonpls123

That's not the answer, it's 20V...I don't know why...

Thanks anyway!!

Reply 3

phys981

AH, sorry, misread. If it's Electric field strength you have to find, then it's volts per metre.

Electric potential changes by 10V between R and S, in a distance of 0.5m

So 10V per =0.5m is 20V per metre.