Circuit Transient

A Capacitor has an initial charge 8.3 coulomb. If the current flows through it is given by the equation i=2t+3 amperes, find the charge when t=1 sec?

• A. 16.3
• B. 12.3.
• C. 4
• D. 6

A coil of inductance 25 H with initial current of 1 ampere is suddenly connected to a source voltage of V=8.9+(3t)^(1/2) volts. What is the current in the inductor after 5sec?

• A. 4.329 A
• B. 4.525 A
• C. 3.329 A
• D. 2.329 A

A coil of 15 H inductance and 10 ohms resistance is suddenly connected to a 20 volts DC source by closing switch. The energy stored in the magnetic field 2 seconds after the switch is closed is;

• A. 16.3 joules
• B. 20 joules
• C. 30 joules.
• D. 10 joules

Find the voltage across a 0.01 micro-farad capacitor at t=0.25 micro-second if v(0)=0.6 volt and the current through it is 0.2sin (2pi10^ 6t) amperes.

• A. 3.18 volts
• B. 3.78 volts
• C. 5.12 volts
• D. 4.56 volts

The rate of rise of current through an inductive coil in maximum

• A. after one time constant
• B. near the final maximum steady value
• C. at the start of current flow
• D. at 63.2% of its maximum steady value