Numbers of electrons pass through lamp in one minute if current applied is 300 mA is:

Options

A. `1.125xx10^(20)`
B. `1.125xx10^(19)`
C. `1.125xx10^(10)`
D. `1.125xx10^(36)`

Explanation

To find the number of electrons passing through a lamp in one minute when a current of 300 mA is applied, we can follow these steps:

### Step 1: Understand the relationship between current, charge, and time
The relationship between current (I), charge (Q), and time (t) is given by the formula:
\[ I = \frac{Q}{t} \]
Where:
- \( I \) is the current in amperes (A)
- \( Q \) is the total charge in coulombs (C)
- \( t \) is the time in seconds (s)

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

### Step 3: Convert time from minutes to seconds
The time given is 1 minute, which we convert to seconds:
\[ t = 1 \, \text{minute} = 60 \, \text{seconds} \]

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

### Step 5: Calculate the number of electrons (n)
The charge of a single electron (e) is approximately \( 1.6 \times 10^{-19} \, \text{C} \). To find the number of electrons, we use the formula:
\[ n = \frac{Q}{e} \]
Substituting the values we have:
\[ n = \frac{18 \, \text{C}}{1.6 \times 10^{-19} \, \text{C/electron}} \]

### Step 6: Perform the calculation
Calculating \( n \):
\[ n = \frac{18}{1.6 \times 10^{-19}} \]
\[ n = 11.25 \times 10^{19} \]
\[ n = 1.125 \times 10^{20} \]

### Final Answer
The number of electrons passing through the lamp in one minute is:
\[ n \approx 1.125 \times 10^{20} \]