Q. A charged particle moves in a magnetic field. What is the path of the particle if it enters the field perpendicularly? (2023)
A.Straight line
B.Circular path
C.Elliptical path
D.Parabolic path
Solution
A charged particle moving perpendicularly to a magnetic field experiences a magnetic force that acts as a centripetal force, causing it to move in a circular path.
Q. A current-carrying conductor experiences a force in a magnetic field. What is the direction of this force? (2020)
A.Parallel to the field
B.Opposite to the field
C.Perpendicular to both current and field
D.In the direction of current
Solution
According to Fleming's left-hand rule, the force on a current-carrying conductor in a magnetic field is perpendicular to both the current and the magnetic field.
Correct Answer: C — Perpendicular to both current and field
Q. If the magnetic field strength is doubled, what happens to the force experienced by a current-carrying conductor? (2022)
A.It doubles
B.It halves
C.It remains the same
D.It quadruples
Solution
The force experienced by a current-carrying conductor in a magnetic field is directly proportional to the magnetic field strength. Therefore, if the magnetic field strength is doubled, the force also doubles.
Q. What happens to the magnetic field when the distance from a long straight conductor is doubled? (2023)
A.It doubles
B.It halves
C.It remains the same
D.It quadruples
Solution
The magnetic field around a long straight conductor decreases with distance. Specifically, it is inversely proportional to the distance from the conductor.
