Question

According to the Biot-Savart Force Law and the right hand rule, if a magnetic field is directed rightward (+ x axis) and a positive test charge moves through the field downwards (- y axis), which direction will the magnetic force be applied onto the charge?

1. upwards (+ y axis)
2. leftward (- x axis)
3. out of the screen (+z axis)
4. into the screen (- z axis)

Answer 1

the direction would go upwards(+yaxis)

Answer 2

3. out of the screen (+z axis)

Step-by-step explanation:

As we know that magnetic force on a positive moving charge is given by

`\vec F = q(\vec v * \vec B)`

here we know that

`\vec B` = Towards right (+X)

`\vec v` = downwards (-Y)

charge is given as positive charge

now as per above formula we have

`\vec F = q(v (-\hat j) * B \hat i)`

`\vec F = qvB \hat k`

so the force will be out of the screen (+Z) direction