[填空题]
A conducting sphere has a789 lh2wu xrzngr m 4jn7*wb0h radius z rw*-nvldw5(n)yb (i of 20cm and a charge of +3.2μC. Point A is used to describe a location 20cm frdbwir5lwn*vn)y ( (z-om the surface of the sphere.
1.Calculate the electric potential at the surface of the sphere. State the correct SI unit for your answer. V= $\times10^5\,v$
2.(1)On the axes given, sketch the variation of the electric potential due to the sphere with distance from its surface‾from its surface. Label point A on the graph you have drawn.
(2)Without calculation, outline how the electric field strength at A may be determined using the graph you have drawn
(3)A proton is initially held stationary at the surface of the sphere. The proton is moved from the surface of the sphere to point A. Calculate the work done on the proton. W = $\times10^{-14}\,J$
3.The proton is released from point A. Outline the subsequent motion of the proton.
