If potential difference across two plates of a capacitor is doubled, then energy stored in it will be:

• A) Four times
• B) Two times
• C) Eight times
• D) Remains same

The primary of a 3:1 step-up transformer is connected to a source and the secondary is connected to a resistor R. The power dissipated by R in this situation is P. If R is connected directly to the source it will dissipate a power of:

• A) P
• B) P/3
• C) P/9
• D) 3P

What does Faraday's law of electromagnetic induction state regarding induced EMF?

• A) The induced EMF is directly proportional to the magnetic field strength.
• B) The induced EMF is independent of the magnetic flux.
• C) The induced EMF is directly proportional to the rate of change of magnetic flux.
• D) The induced EMF is directly proportional to the magnetic flux.

If velocity of a conductor moving through a magnetic field B is made zero then motional emf is:

• A) -v/LB
• B) -vBL
• C) Zero
• D) -BL/v

Power of an electric generator of voltage (V) and driving current (I) through an appliance is:

• A) I/Q
• B) VR
• C) IR
• D) V2/R

According to Coulomb's law, as the distance between two charges increases:

• A) The force becomes zero
• B) The force decreases
• C) The force remains constant
• D) The force increases

Electromagnetic waves were experimentally discovered by:

• A) Einstein
• B) Hertz
• C) Maxwells
• D) Ampere

The lenz’s law refers to:

• A) Potential difference
• B) Induced potential
• C) Motional emf
• D) Induced current

A charge Q is moving with a velocity (v) parallel to a magnetic field (B) . Force on the charge due to magnetic field is:

• A) Constant
• B) Maximum
• C) Minimum
• D) Zero

Which of the following units is used to measure Electromotive Force?

• A) Joule
• B) Ampere
• C) Newton
• D) Volt

The amplitude modulation frequency ranges from:

• A) 540 kHz to 1600 kHz
• B) 520 kHz to 1600 kHz
• C) 540 kHz to 1000 kHz
• D) 540 kHz to 1400 kHz

Why does Lenz's Law dictate that the induced current opposes the change in magnetic flux?

• A) To maximize magnetic flux
• B) To amplify the induced EMF
• C) To conserve energy
• D) To increase energy consumption

Transformers are used in:

• A) DC circuit only
• B) Neither in DC nor in AC circuits
• C) Both DC and AC circuits
• D) AC circuits only

For a point charge, the electric field lines are always ____________ to equipotential surfaces.

• A) Randomly oriented
• B) Parallel
• C) Perpendicular
• D) Tangential

An LC series circuit with an inductance L and a capacitance C has an oscillation frequency f. Two inductors, each with inductance L, and two capacitors, each with capacitance C, are all wired in series and the circuit is completed. The oscillation frequency is:

• A) f/2
• B) 2f
• C) f/4
• D) f

When some dielectric is inserted between the plates of a capacitor, then capacitance:

• A) Infinity
• B) Zero
• C) Increased
• D) Decreased

Under what condition does Ohm's Law hold true?

• A) When the temperature is constant
• B) When the voltage is fluctuating
• C) When the circuit is open
• D) When the resistance is not constant

The increase in capacitance of a capacitor due to presence of dielectric is due to:

• A) Electrolysis
• B) Electric polarization
• C) Electrification
• D) Ionization

The electric potential at the center of a dipole is

• A) Maximum
• B) Twice of field of point charge
• C) Same as field of point charge
• D) Zero

The value of k in coulomb's law depends upon

• A) distance between charges
• B) magnitude of charges
• C) all of these
• D) medium between two charges