Moving Charges and Magnetism is a core Class 12 Physics chapter that connects electricity with magnetism through the ideas of magnetic force on moving charges, magnetic fields due to currents, and motion of charged particles in magnetic fields. These concepts form the basis of many standard CBSE board questions and are repeatedly used in numericals involving Lorentz force, Biot–Savart law, Ampere’s circuital law, and force between current-carrying conductors.
This chapter is also crucial for understanding real devices and experiments such as cyclotrons, moving-coil galvanometers, current balance definition of ampere, and magnetic field mapping for common current geometries (wire, loop, solenoid, toroid). Mastery of key formulae, vector directions (right-hand rules), and typical approximations helps in scoring well in both CBSE board-level problems and JEE/NEET-aligned MCQs.
30
Minutes
30
Questions
1 / -0
Marking
Q1. A charge moves with velocity in a uniform magnetic field . The magnetic force on it is maximum when the angle between and is:
Q2. A proton enters a uniform magnetic field with velocity perpendicular to . The path followed is:
Straight line
Parabola
Circle
Helix
Q3. The radius of circular path of a charged particle (charge , mass ) moving with speed perpendicular to a uniform magnetic field is:
Q4. The time period of a charged particle in uniform circular motion in a magnetic field (with velocity perpendicular to ) is:
Q5. A charged particle enters a uniform magnetic field with velocity having components and relative to . Its trajectory is:
Straight line along
Circle
Helix
Parabola
Q6. The pitch of the helical path of a charged particle moving in a uniform magnetic field is:
Q7. A charged particle moves in a uniform magnetic field. The work done by magnetic force on the particle is:
Maximum
Minimum but non-zero
Zero
Depends on speed
Q8. SI unit of magnetic field is:
Weber
Tesla
Henry
Coulomb
Q9. The magnetic field at a distance from a long straight wire carrying current in free space is:
Q10. Two long parallel wires carry currents and in the same direction. The force between them is:
Repulsive
Attractive
Zero
Alternating between attractive and repulsive
Q11. The force per unit length between two long parallel wires separated by distance , carrying currents and , is:
Q12. A current-carrying conductor of length carrying current is placed in a uniform magnetic field . The force on it is maximum when the angle between conductor (current direction) and is:
Q13. A circular loop of radius carrying current produces magnetic field at its center:
Q14. For a circular coil of turns, radius , carrying current , the magnetic field at the center is:
Q15. Magnetic field inside a long solenoid having turns per unit length carrying current is:
...and 15 more challenging questions available in the interactive simulator.