Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NTA Abhyas JEE Main2020PhysicsAlternating CurrentPractice

A power transmission line feeds input power at 2400   V to a step-down transformer and which delivers power at 240   V with its primary windings having 5000 turns. If the current in the primary coil of the transformer is 5   A and its efficiency is 80 % , then what is the output current (in A )?

Correct answer

40

Step-by-step solution

ε p = 2400 V , N p = 5000 ε s = 240 V , I p = 5 A efficiency, η = 80 % = 0 . 8 , I s = ? η = P 0 P i = ε s I s ε p I p ⇒ I s = η ε p I p ε s = 0 . 8 × 2400 × 5 240 = 40 A

Practice Alternating Current on Quantrex Academy →

More from Alternating Current

Consider a circuit consisting of a capacitor of capacitance C and a coil with N turns per unit length, cross sectional area S and length d , where d^2 S . There is another coil of 2026An LCR series circuit driven with E_ rms = 90 V at frequency f_d = 30 Hz has resistance R = 80 , , an inductance with inductive reactance X_L = 20.0 , and capacitance with capacitiv 2026A series LCR circuit with R = 20 , L = 1.6 H and C = 40 F is connected to a variable frequency a.c. source. The inductive reactance at resonant frequency is _______ . 2026An a.c. source of angular frequency is connected across a resistor R and a capacitor C in series. The current is observed as I . Now the frequency of the source is changed to /4 , 2026An inductor of 10 mH, capacitor of 0.1 F and a resistor of 100 are connected in series across an a.c power supply 220 V, 70 Hz. The power factor of the given circuit is 0.5 . The d 2026The figure given below shows an LCR series circuit with two switches S₁ and S₂ . When switch S₁ is closed keeping S₂ open, the phase difference ( ) between the current and source v 2026An inductor stores 16 J of magnetic field energy and dissipates 32 W of thermal energy due to its resistance when an a.c. current of 2 A (rms) and frequency 50 Hz flows through it. 2026The electric current in the circuit is given as i=i_ o (t / T) . The r.m.s current for the period t=0 to t=T is _ _ _ _ . 2026 Full Alternating Current list All NTA Abhyas JEE Main PYQs