Question

. A negative charge is moving upwards in a magnetic field directed towards north. The particle will be deflected towards
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Answer 1

Given:

A negative charge is moving upwards in a magnetic field directed towards north.

To find:

The direction of deflection of particle.

Calculation:

So, as the negative charge moves upwards in the magnetic field , the force will be towards ;

$\therefore \: \rm{ \vec{f} = (- q)( \vec{v} \times \vec{B})}$

$= > \: \rm{ \vec{f} = (- q) \{ v \hat{j} \times B (- \hat{ k}) \}}$

$= > \: \rm{ \vec{f} = ( q) \{ v \hat{j} \times B (\hat{ k}) \}}$

$= > \: \rm{ \vec{f} = ( qv B) \hat{i}}$

So, the force experienced by the charge is towards east.

Hence , the particle will be deflected towards east.

• Since a negative charge has been given, the same result can be obtained by using the Fleming's Left Hand Rule.

• If the same question had been given with a positive charge , then you need to use Fleming's Right Hand Rule.

Refer to the attached diagram.

Answer 2

Answer:

Given:

A negative charge is moving upwards in a magnetic field directed towards north.

To find:

The direction of deflection of particle.

Calculation:

So, as the negative charge moves upwards in the magnetic field , the force will be towards ;

So, the force experienced by the charge is towards east.

Hence , the particle will be deflected towards east.

Since a negative charge has been given, the same result can be obtained by using the Fleming's Left Hand Rule.

If the same question had been given with a positive charge , then you need to use Fleming's Right Hand Rule.

Refer to the attached diagram.

Explanation: