One charged plastic ball is vertically above another in a test tube as shown.The balls are in equilibrium a distance d apart. If the charge on each ball is doubled,the distance between the balls in the test tube would become
A) d.
B)2d.
C)4d.
D)8d.

Question

One charged plastic ball is vertically above another in a test tube as shown.The balls are in equilibrium a distance d apart.  If the charge on each ball is doubled,the distance between the balls in the test tube would become
A) d. 
B)2d. 
C)4d. 
D)8d.

Quizplus · Accepted Answer

The force of attraction or repulsion between two charged objects is proportional to the product of the charges and inversely proportional to the square of the distance between them. In this case, since the charges on both balls are doubled, the force between them will increase by a factor of 4 (2 times 2). To maintain equilibrium, the distance between the balls must be increased by a factor of 2 to compensate for the increased force. Therefore, the new distance between the balls will be 2d.

One Charged Plastic Ball Is Vertically Above Another in a Test