Chapter 20, Problem 17Q

To determine

To determine:

The two possible situations in a nonzero magnetic field such that a charged particle moves in a straight line.

Answer to Problem 17Q

Solution:

Yes, there could be a nonzero magnetic field in this region.

The two possible situations are,

(1)When a charged particle is moving along or opposite to magnetic field

(2)when force due to electric field and magnetic field cancel each other.

Explanation of Solution

Explanation:

The force on a charge particle in a magnetic field is given by, $F=Bqv\sin \theta$ where ϴ is the angle between B and v. Even if B is nonzero, F is zero if $\theta =0^o$ or $\theta ={180}^o$ i.e. when a charged particle is moving along or opposite to magnetic field.

Another possible situation is, by applying suitable electric field, perpendicular to magnetic field such that force due to electric field and force due to electric field cancels each other.

Conclusion:

Yes, there could be a nonzero magnetic field in this region.

The two possible situations are,

(1)When a charged particle is moving along or opposite to magnetic field

(2)when force due to electric field and magnetic field cancel each other.