The direction of the magnetic force exerted on the proton is positive y-direction.
Here proton(positively charged) moves in the positive x direction in a region where there is a magnetic field in the negative z direction. To find the direction of the magnetic force exerted on the proton, the magnetic force is given by:
[tex]F_{B} = B[/tex]×[tex]q[/tex]×vsinθ
The vector v x B points along the positive y-direction. (Right-hand thumb rule). For a proton, q is positive, so the Force vector F = q v x B also points along the positive y-direction. With a force on it in the positive y-direction, the proton will move in a circle in a plane parallel to the XY-plane.
[tex]F_{B} = qV[/tex]×[tex]B[/tex]
[tex]F_{B}[/tex] = i ×(-k) = +j
Hence magnetic force acts in the positive y-direction.
To know more about charge moving in Magnetic fields kindly refer to the below link:
https://brainly.com/question/27129640
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