Question

Which of the following statements are true?
True False  Magnetic field lines always start at a North and end at a South pole.
True False  When placing a dipole magnet into a magnetic field, it will be accelerated perpendicular to the field lines.
True False  The force on a moving charge is perpendicular to both the field and its velocity.
True False  The larger the charge of a moving particle, the more it will accelerate inside of a magnetic field.

Answer 1

1) FALSE: Magnetic field lines always start at a North and end at a South pole.

Magnetic field lines outside the magnet travel from the North to the South pole; however, magnetic field lines are closed loops, thus within the magnet, the direction of the field lines will be from the South pole to the North pole.

2) TRUE: When placing a dipole magnet into a magnetic field, it will be accelerated perpendicular to the field lines.

The given statement is true because if a dipole magnet is placed in a magnetic field then it will accelerate perpendicularly to the magnetic field because torque as on it and is given by,

τ=μ×B

Here, μ is the dipole moment.

3) TRUE: The force on a moving charge is perpendicular to both the field and its velocity.

The given statement is true because the force on moving charged particle is perpendicular to both the field and its velocity and it is given by right-hand rule. Given by

F=q(v×B)

4)TRUE

force F=q(v×B)