Practice MCAT Question - Q25 - Answer!
In the figure below, points A, B, and C are at various distances from a given point
charge.
Which statement is most accurate? The electric field strength is
A. greatest at point A.
B. greatest at point B.
C. greatest at point C.
D. the same at all three points.
The correct answer is (C). From Coulomb’s law, force varies inversely with the square of the distance from the charge. The strength of the electric field at a point is the ratio of this force to the charge:
E = F/q = (k(q1q2)/r2)/q
Therefore, E and r2 are inversely proportional. The smaller the value of r, the smaller the value of r2 and the greater the value of E.
