The number of turns becomes double, but length remain same, then magnetic field in the solenoid become

• A) Half
• B) Remain same
• C) Double
• D) Zero

What is the role of an EMF source, such as a battery, in an electrical circuit?

• A) To provide energy to the circuit
• B) To resist the flow of current
• C) To measure electrical potential
• D) To act as a short circuit

If a conductor is placed between the plates of a capacitor, what will happen to the potential difference between the plates?

• A) It will increase
• B) It will become zero
• C) It will be maintained
• D) It will decrease

Which one of the following is the velocity of a carrier wave?

• A) 3 × 109 ms-1
• B) 3 × 1010 ms-1
• C) 3 × 106 ms-1
• D) 3 × 108 ms-1

Work done on a charged particle moving in uniform magnetic field is:

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

The focal length of convex lens is:

• A) Negative
• B) Small
• C) Positive
• D) Large

One Tesla is equal to

• A) N /Am
• B) N /A m
• C) N A/m
• D) N A m

The reaction of an induction at 50 Hz is 10 Ω, its reactance at 100 Hz becomes:

• A) 2.5 Ω
• B) 20 Ω
• C) 5 Ω
• D) 1 Ω

In the context of a charged particle moving perpendicular to the magnetic field, If both the velocity (v) and the magnetic field strength (B) are doubled while keeping the charge (q) and mass (m) constant, what happens to the orbital radius (r)?

• A) No change in the orbital radius.
• B) Orbital radius quadruples.
• C) Orbital radius doubles.
• D) Orbital radius halves.

What is the direction of the force between two charges according to Coulomb's law?

• A) Depends on the polarity of the charges
• B) Perpendicular to each other
• C) Away from each other
• D) Towards each other

Consider the following statements, and then select the correct ones. I. Most of the electrical devices we use require AC voltage. II. Most of the electrical energy sold by power companies is transmitted and distributed as alternating current. III. AC voltage can be easily and efficiently converted from one place to another by means of transformers.

• A) I, II, and III are correct.
• B) I and II are correct, and III is incorrect.
• C) I is correct, and II and III are incorrect.
• D) I and III are correct; II is incorrect.

In the context of magnetic force, if the velocity vector v is perpendicular to the magnetic field vector B, the resulting force vector F will be:

• A) Minimum
• B) Zero
• C) Can not be determined
• D) Maximum

Work done between two points on equipotential surface is

• A) Zero
• B) Maximum
• C) Negative
• D) Infinite

The current in a car headlamp is 2.0 A. The headlamp is switched on for 3.0 minutes. How much charge passes through the headlamp?

• A) 2.0 C
• B) 90 C
• C) 360 C
• D) 4.0 C

If the velocity of a charged particle in perpendicular electric and magnetic field is 7.27 x 106 m/s and the Electric field is 6 x 106 N/c, what should be the value of the magnetic field?

• A) 0.45 T
• B) 0.83 T
• C) 0.78 T
• D) 0.94 T

In what paths do eddy currents typically circulate within a conductor?

• A) random patterns
• B) Elliptical or circular paths
• C) Spiral paths
• D) Straight lines

The transformer voltage induced in the secondary coil of a transformer is mainly due to:

• A) A varying electric field
• B) A varying magnetic field
• C) The vibrations of the primary coil
• D) The iron core of the transformer

Why is the work done by the magnetic force always zero on a charged particle?

• A) The force and velocity vectors are parallel.
• B) The velocity of the particle is small.
• C) The force and velocity vectors are perpendicular.
• D) The magnetic force is weak.

If a charged particle moves in a magnetic field, what effect does the magnetic force have on the kinetic energy of the particle?

• A) It increases the kinetic energy.
• B) It stops the particle.
• C) It decreases the kinetic energy.
• D) It does not change the kinetic energy.

The wave form of alternating voltage is a:

• A) Sine wave
• B) Tangent wave
• C) Contingent wave
• D) Cosine wave