Question

A uniform (Constant in magnitude and direction) electric field has magnitude E and is directed in the negative x direction. The potential difference between point a (at x= 0.50 m ) and point b (at x= 0.85 m ) is 370 V.

A) Calculate the value of E

B) A negatively charged point charge q=−0.200μC is moved from b to a. Calculate the work done on the point charge by the electric field.

Answer 1

A uniform electric field has magnitude E and is directed in the negative x direction.

As potential falls in the direction of field, the potential is increasing on positive x axis

The potential difference between point a (at x= 0.50 m) and point b (at x= 0.85 m) is 370 V.

Point b is at the higher potential

______________________

(A) E =-(Vb-Va)/[0.85-0.50]

E =370 /0.35

E = 1057.14 N/C

_______________________-------

(B)

Work = qV = -0.2*10^-6*370

work = -7.5*10^-5 J

the work done on the point charge by the electric field is -7.5*10^-5 J