NEET-XII-Physics
02: Electrostatic Potential And Capacitance
- #12A charge of 8 mC is located at the origin. Calculate the work done in taking a small charge of -2 × 10-9 C from a point P (0, 0, 3 cm) to a point Q (0, 4 cm, 0), via a point R (0, 6 cm, 9 cm).
Ans : Charge located at the origin, q = 8 mC= 8 × 10-3 C
Magnitude of a small charge, which is taken from a point P to point R to point Q, q1 = - 2 × 10-9 C
All the points are represented in the given figure.
Point P is at a distance, d1 = 3 cm, from the origin along z-axis.
Point Q is at a distance, d2 = 4 cm, from the origin along y-axis.
Potential at point P,
Potential at point Q,
Work done (W) by the electrostatic force is independent of the path.
Therefore, work done during the process is 1.27 J.