An experiment is set up to investigate the behaviour of electrons in electric fields - Scottish Highers Physics - Question 7 - 2016

The number of electrons can be calculated using the formula: $Q = It$ Where:

• $Q$ is the total charge,
• $I$ is the current ($8.0 \text{ mA} = 0.008 \text{ A}$),
• $t$ is the time (in seconds, $1 \text{ minute} = 60 \text{ s}$).

First, we calculate the total charge in one minute: $Q = (0.008)(60) = 0.48 \text{ C}$

Next, we find the number of electrons: The charge of one electron is $1.6 \times 10^{-19} \text{ C}$, hence: $\text{Number of electrons} = \frac{Q}{q} = \frac{0.48}{1.6 \times 10^{-19}} = 3.0 \times 10^{18}$

Therefore, the number of electrons passing between the metal plates in one minute is approximately $3.0 \times 10^{18}$.

To represent the electric field pattern:

• Draw straight lines with arrows pointing downwards between the two metal plates, indicating the direction of the electric field.
• Ensure that the spacing between the lines is uniform, showing an approximately equal field strength.
• The lines should start and finish on the plates, maintaining right angles to the plates.