Question

Four point charges are arranged in the configuration below. Each grid unit is 1 m.

+4μc (0,2) +2μC -2μα +4με m

1)  What is the direction of the FORCE that the +2mC charge exerts on the 4mC at the origin?

+x-direction

+y-direction

-x-direction

-y-direction

the force is zero

2)  What is the direction of the FORCE that the -2mC charge AND the +4mC at the origin exert on the +2mC charge?

+x-direction

+y-direction

-x-direction

-y-direction

the force is zero

Answer 1

Solution: (1) The electric force directs from positive charge to negative charge. Here, the charge at the left hand side exerts a force on the charge at the origin. The direction of the force is away from the charge. Hence, the direction is along the +X axis. (2) The force due to the -2 uC charge on the +2 °C is along the +X direction. The force due to the +4 4C charge on the +2 uC is along the -X direction. Since the force is greater due to the +4uC charge on the +2 uc. The net force along the +X direction.