Final answer:
Using the right-hand rule, the force on a negative charge moving in a magnetic field depicted by the equation would be directed along the positive x-axis. Therefore, the direction of the force, measured counterclockwise from the negative x-axis, would be 180 degrees.
Step-by-step explanation:
The question concerns the magnetic force experienced by a charge moving in a magnetic field. According to the provided equation F = qᵢ x B = (5.0 × 10⁻⁹C) ((2.0⁻⁻ᵣ⁺⁰.0k) x 10⁴m/s) x (1.5T), the cross-product is used to calculate the force on a charge due to a magnetic field. In terms of directionality, the right-hand rule is typically applied: point your fingers in the direction of the velocity (negative y-direction for the velocity vector), sweep your fingers in the direction of the magnetic field (positive z-direction for the magnetic field vector), and your thumb will then point in the direction of the force exerted on a positive charge (negative x-direction in this case).
For a negative charge, the direction of the force would be opposite to that of a positive charge. So, considering a negative charge and the right-hand rule, the force direction would be positive x-direction. To express the direction of the force as an angle measured counterclockwise from the −x-axis, the angle would be 180 degrees.