1

**Physics, Astronomy & Cosmology / electrics exam question**

« **on:**21/04/2007 22:43:12 »

Well thats the whole of the first part of the question. I thought that if u answered that, then i could do the second part myself. But, ow well...

"The potential at A is removed and it is insulated from the ground instead. Potential at B is raised to 300V, at which point the potential at A is measured to be 40V."

1) What is the potential at X now?

2) Having measured 40V at end B initially, why is it that 40V has also been required at end A for the second measurement?

3) What is the potential gradient from B to X?

4) Why is the potential gradient from A to X the same as B to X

5) From the two potential gradients obtained earlier, deduce the value of d.

"The potential at A is removed and it is insulated from the ground instead. Potential at B is raised to 300V, at which point the potential at A is measured to be 40V."

1) What is the potential at X now?

2) Having measured 40V at end B initially, why is it that 40V has also been required at end A for the second measurement?

3) What is the potential gradient from B to X?

4) Why is the potential gradient from A to X the same as B to X

5) From the two potential gradients obtained earlier, deduce the value of d.