Answer:
The correct option is A: 4.29 N.
Step-by-step explanation:
The magnetic force is given by:
[tex] F = qv\times B = qvBsin(\theta) [/tex]
Where:
q: is the charge = 7.12x10⁻⁶ C
v: is the speed = c/2 = 1.5x10⁸ m/s
B: is the magnetic field = 4.02x10⁻³ T
θ: is the angle = 90° (the speed is perpendicular to the magnetic field)
Hence, the force on the charge is:
[tex]F = qvBsin(90) = 7.12 \cdot 10^{-6} C*1.5 \cdot 10^{8} m/s*4.02 \cdot 10^{-3} T = 4.29 N[/tex]
Therefore, the correct option is A: 4.29 N.
I hope it helps you!