Question Detail

For the particle to remain stationary, the upward electric force must balance the downward gravitational force. Gravitational force: F_g = mg Electric force: F_e = qE Given: mass m = 5 g = 0.005 kg, Electric field E = 800 N/C, acceleration due to gravity g = 9.8 m/s². Equating forces: qE = mg q = mg/E = (0.005 kg * 9.8 m/s²) / 800 N/C = 0.049 / 800 C = 0.00006125 C = 61.25 µC. Since the gravitational force is downward and the electric field is downward, the electric force must be upward to keep the particle stationary. For the electric force (F_e = qE) to be upward when E is downward, the charge 'q' must be negative. Therefore, the charge is -61.25 µC, which is approximately -61.3 µC. (Note: The options in the original image contain a typo, using 'µF' instead of 'µC'.)