A conductor carries a current of 300 mA. The number of electrons passing through it in 1 minute are about

Options

A. `1.125xx10^(17)`
B. `1.125xx10^(20)`
C. `1.125xx10^(23)`
D. `1.125xx10^(25)`

Explanation

To find the number of electrons passing through a conductor carrying a current of 300 mA in 1 minute, we can follow these steps:

### Step 1: Understand the relationship between current, charge, and time
The current (I) is defined as the rate of flow of charge (Q) over time (t):
\[ I = \frac{Q}{t} \]
Where:
- \( I \) is the current in amperes (A)
- \( Q \) is the charge in coulombs (C)
- \( t \) is the time in seconds (s)

### Step 2: Convert the current from milliamperes to amperes
Given:
\[ I = 300 \, \text{mA} = 300 \times 10^{-3} \, \text{A} = 0.3 \, \text{A} \]

### Step 3: Convert the time from minutes to seconds
Since we need to calculate the charge over 1 minute:
\[ t = 1 \, \text{minute} = 60 \, \text{seconds} \]

### Step 4: Calculate the total charge (Q) flowing through the conductor in 1 minute
Using the formula \( Q = I \times t \):
\[ Q = 0.3 \, \text{A} \times 60 \, \text{s} = 18 \, \text{C} \]

### Step 5: Determine the charge of a single electron
The charge of a single electron (e) is approximately:
\[ e = 1.6 \times 10^{-19} \, \text{C} \]

### Step 6: Calculate the number of electrons (n) passing through the conductor
Using the formula:
\[ n = \frac{Q}{e} \]
Substituting the values we have:
\[ n = \frac{18 \, \text{C}}{1.6 \times 10^{-19} \, \text{C}} \]

### Step 7: Perform the calculation
Calculating \( n \):
\[ n = \frac{18}{1.6 \times 10^{-19}} \]
\[ n = 11.25 \times 10^{19} \]
\[ n = 1.125 \times 10^{20} \]

### Conclusion
The number of electrons passing through the conductor in 1 minute is approximately:
\[ n \approx 1.125 \times 10^{20} \]