Question

When a glass rod is rubbed with silk thread, it loses 1000 electrons. Then the charge on the glass rod is (electronic charge $e = 1.6 \times 10^{-19}$ C)

• A. $+1.6 \times 10^{-16}$ C
• B. $-1.6 \times 10^{-19}$ C
• C. $-1.6 \times 10^{-13}$ C
• D. $+1.6 \times 10^{-19}$ C
• E. $-1.6 \times 10^{-15}$ C

Hint:

When an object loses electrons, it becomes positively charged. When it gains electrons, it becomes negatively charged.

Answer 1

The Correct Option is A

Step 1: The charge on a single electron is: \[ e = 1.6 \times 10^{-19} { C} \] 
Step 2: The charge on the glass rod is given by: \[ Q = n e \] where $n$ is the number of lost electrons. Given that $n = 1000$, we get: \[ Q = 1000 \times 1.6 \times 10^{-19} \] \[ Q = 1.6 \times 10^{-16} { C} \] 
Step 3: Since the rod loses electrons, it becomes positively charged. 
Step 4: Therefore, the correct answer is (A).