Two spheres of equal mass A and B are given +q and -q charge respectively then

Options

A. mass of A increases
B. mass of B increases
C. mass of A remains constant
D. mass of B decreases

Answer

To solve the problem, we need to analyze the effect of charging two spheres, A and B, with charges +q and -q respectively. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Charges
- Sphere A is given a positive charge (+q).
- Sphere B is given a negative charge (-q).

### Step 2: Analyze Electron Transfer
- To give Sphere A a positive charge, electrons must be removed from it. This means that Sphere A loses mass equivalent to the mass of the electrons removed.
- To give Sphere B a negative charge, electrons must be added to it. This means that Sphere B gains mass equivalent to the mass of the electrons added.

### Step 3: Calculate the Mass Change
- The mass of an electron is approximately \(9.1 \times 10^{-31}\) kg.
- If Sphere A loses electrons, its mass decreases.
- If Sphere B gains electrons, its mass increases.

### Step 4: Conclusion on Mass Change
- Since Sphere A loses mass and Sphere B gains mass, we can conclude:
- The mass of Sphere A decreases.
- The mass of Sphere B increases.

### Final Answer
- Therefore, the mass of Sphere B increases while the mass of Sphere A decreases.