Two very small plastic balls of equal mass are released from

Two very small plastic balls of equal mass are released from rest. One of them carries +10 mu C of excess charge and the other one carries +1 mu C of charge. No other charges or fields are present. Which of the following statements are true about them as they move away from each other? (There may be more than one correct choice.) The balls always have accelerations of equal magnitude. The acceleration of the balls keeps increasing. The acceleration of the 10-mu C ball is 10 times that of the 1-mu C ball. The speed of the balls keeps increasing. The acceleration of the 1-mu C ball is 10 times that of the 10-mu C ball.

Solution

The force between the two balls is elctrostatic

F = kq₁q₂ /r² = 9.0e+9*10.0e-6*1.0e-6/r² = 0.09/r²

The force is mutul and each ball expriencs the same force. As the mass of the balls is same

acceleration   a = F/m is of equal magnitude, it always remains same   -----(A)

As th balls always experience a +v acceleration, the speed of the balls keep increasing --------(D)