3. A strong lightning bolt transfers about 25 C to Earth. How many electrons are transferred?

To determine the number of electrons transferred when a strong lightning bolt transfers about 25 C to Earth, we need to use the elementary charge of an electron, which is approximately \(1.602 \times 10^{-19}\) coulombs.<br /><br />The number of electrons transferred can be calculated using the formula:<br /><br />\[ \text{Number of electrons} = \frac{\text{Total charge transferred}}{\text{Elementary charge of an electron}} \]<br /><br />Given:<br />- Total charge transferred = 25 C<br />- Elementary charge of an electron = \(1.602 \times 10^{-19}\) C<br /><br />Substitute these values into the formula:<br /><br />\[ \text{Number of electrons} = \frac{25 \, \text{C}}{1.602 \times 10^{-19} \, \text{C/electron}} \]<br /><br />Perform the division:<br /><br />\[ \text{Number of electrons} = \frac{25}{1.602 \times 10^{-19}} \]<br /><br />\[ \text{Number of electrons} \approx 1.57 \times 10^{20} \]<br /><br />Therefore, approximately \(1.57 \times 10^{20}\) electrons are transferred when a strong lightning bolt transfers about 25 C to Earth.