NEET2026PhysicsChapterActual
The figure shows a branch of an electrical circuit. At a given instant, the current I flowing from Q to P is 3 A and it is decreasing at a rate of 4 A/s . If point Q is connected to the ground, what is the electric potential at point P?
Options
- A-8 V
- B+4 V
- C-4 V
- D-16 V
Correct answer
C. -4 V
Step-by-step solution
Applying Kirchhoff's Voltage Law (KVL) from point Q to point P, we can write the equation for the potential difference: V_Q - I R - L dI dt + E = V_P Given the parameters in the problem: Point Q is grounded, so V_Q = 0 V . The current I flowing from Q to P is 3 A . The current is decreasing at a rate of 4 A/s , so the rate of change of current is dI dt = -4 A/s . The resistance R = 4 . The inductance L = 0.5 H . The battery has an EMF E = 6 V . Traversing from Q to P, we move from the negative (shorter, thicker lin