Concepts Of Physics MCQ Edition [Volume 1]PhysicsPhysics and Mathematics
In a discharging R – C circuit, the electric current is given by i = i₀ e^ -t/RC , where i₀ , R and C denote constant parameters and t represents time. If i₀ = 2.00 A , R = 6.00 10^5 and C = 0.500 F , determine the current at t = 0.3 s .
Options
- A1.00 e A
- B2.00e A
- C2.00 e^2 A
- D2.00 e A
Correct answer
D. 2.00 e A
Step-by-step solution
Given parameters are i₀ = 2.00 A , R = 6.00 10^5 , C = 0.500 10⁻⁶ F , and t = 0.3 s . The time constant of the circuit is calculated as: RC = (6.00 10^5) (0.500 10⁻⁶) = 3.00 10⁻¹ s = 0.3 s The current at time t is given by the equation: i = i₀ e^ -t/RC Substituting the values into the equation: i = 2.00 e^ -0.3/0.3 i = 2.00 e⁻¹ = 2.00 e A