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Given a magnetic field B, a charge Q, and the charge's velocity v, which statement is true?

-The magnetic force is maximized when the charge is moving perpendicular to the magnetic field lines.

-The magnetic force is maximized when the charge is moving parallel to the magnetic field lines.

-The magnetic force is maximized when the charge is stationary.

-None of the above.

User Lekesha
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Final answer:

The magnetic force is maximized when the charge Q is moving perpendicular to the magnetic field lines B, because that orientation results in sin(90°) = 1, giving the maximum force F = qvB.

Step-by-step explanation:

The magnetic force on a charge Q moving with velocity v in a magnetic field B is described by the equation F = qvB sin(θ), where θ is the angle between the velocity and the magnetic field vectors. According to this equation, the force is proportional to the sine of the angle between the velocity of the charge and the direction of the magnetic field.

Therefore, the statement that the magnetic force is maximized when the charge is moving perpendicular to the magnetic field lines is true. This is because when the charge moves perpendicular to the field lines (θ = 90°), sine takes its maximum value of 1, yielding the maximum possible force F = qvB. When a charge moves parallel to the field lines (θ = 0° or 180°), the sine value is 0, which means no magnetic force is exerted on the charge. If the charge is stationary, the velocity v is zero, and therefore, the magnetic force F is also zero.

This magnetic force is always directed perpendicular to both the direction of the charge's velocity and the magnetic field lines, which is illustrated by the right hand rule-1 (RHR-1).

User Yazu
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