Question

Explain magnitude and direction of force.

Answer 1

The magnetic field B is defined from theLorentz Force Law, and specifically from the magnetic force on a moving charge:The implications of this expression include:1. The force is perpendicular to both the velocity v of the charge q and the magnetic field B.2. The magnitude of the force is F = qvB sinθ where θ is theangle < 180 degrees between the velocity and the magnetic field. This implies that the magnetic force on a stationary charge or a charge moving parallel to the magnetic field is zero.3. The direction of the force is given by theright hand rule.The force relationship above is in the form of avector

Answer 2

Answer:

• Current is the rate of flow of charge. So, if a current carrying wire is present in a magnetic field,it experiences a force due to the force on charges moving on it. This was proposed by Ampere.

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$\underline{ \boxed{ \red{ \sf{Direction \: of \: force }}}}:-$

• The direction of force can be found with the help of Fleming's left- hand rule.

• When we stretch the thumb, the forefinger and the Central fingure perpendicular to each other and orient the forefinger along the direction of magnetic field, the Central finger along the direction of current then the thumb point's towards the direction of force.

• It is important to note that first orient the forefinger in the direction of magnetic field.

• Then, orient the Central finger in the direction of current such that the forefinger remains in the direction of the magnetic field.

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$\underline{ \boxed{ \red{ \sf {Magnitude \: of \: force }}}}:-$

• Magnitude of force increases with the increase in the current flowing in the conductor.

$\mapsto \sf F∝L$

• Magnitude of force increase with the increase in the magnetic field.

$\mapsto \sf F∝B</p><p>$

• Magnitude of force also increases with the length of the conductor.

$\mapsto \sf F∝l</p><p></p><p>$

• Magnitude of force depends on the angle theta between current and magnetic field.

$\mapsto \sf F ∝ sin θ$

$\mapsto \sf F ∝BIl \: sin θ$

$\mapsto \sf F = BIl \: sin θ$

$\therefore$ (The proportionality constant has a value of 1 in S.I)