Find the magnitude and direction of the force

AI Thread Summary
A 0.45 T magnetic field directed east exerts a force on a +1.0 µC charge moving south at 3.5 m/s. The magnitude of the force is calculated using the formula F = qvB, resulting in 1.575 x 10^-6 N. The direction of the force is determined using the Left Hand Rule, indicating it is upwards. There was a correction noted regarding the charge value used in the calculation, which should be +1.0 µC instead of 0.1 µC. The discussion clarifies the appropriate rule to use for determining the force direction on a moving charge in a magnetic field.
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Homework Statement



A 0.45 T magentic field points due east. Find the magnitude and direction of the force on a +1.0uC charge moving southward at 3.5 m/s?


Homework Equations



F= qvB
Right hand rule

The Attempt at a Solution



Using right hand rule, direction of the force is up

For mangnitude of the force:
F-qvB
=0.10 x 10^-6 x 3.5 x .45N
=1.575 x 10^-7N

IS this correct? Do I need to show anything else for the direction of the force ?
 
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The answer is 1.575 x 10-6 N
For some reason you used 0.1μC in the calculation instead of 1μC
But yes, the method is correct.
The direction of the force is given by the Left Hand Rule.
Pointer finger to the East - field
Centre finger points South - current
Thumb upwards - force
So "upwards" is correct but you used the wrong rule!
The Right Hand Rule is used to find the direction of the induced emf in a wire that is moved in a magnetic field.
The Left Hand Rule is used to find the direction of the force on a moving charge or current in a magnetic field.
 
Thank you so much.
 
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