A transformer consisting of 300 turns in the primary and 150 turns in the secondary gives output power of 2.2 kW. If the current in the secondary coil is 10A, then the input voltage and current in the primary coil are :

A circuit connected to an ac source of emf e = e₀sin(100t) with t in seconds, gives a phase difference of $$\pi $$/4 between the emf e and current i. Which of the following circuits will exhibit this ?

An alternating voltage v(t) = 220 sin 100 $$\pi $$t volt is applied to a purely resistance load of 50$$\Omega $$ . The time taken for the current to rise from half of the peak value to the peak value is :

In the above circuit, C = $${{\sqrt 3 } \over 2}$$$$\mu $$F, R₂ = 20 $$\Omega $$, L = $${{\sqrt 3 } \over {10}}$$ H and R₁ = 10 $$\Omega $$. Current in L-R₁ path is I₁ and in C-R₂ path it is I₂ . The voltage of A.C. source is given by, V = 200 $${\sqrt 2 }$$ sin (100 t) volts . The phase difference between I₁ and I₂ is :