A proton enters a region of magnetic field as shown - Scottish Highers Physics - Question 10 - 2018

To determine the direction in which the proton will deflect when it enters the magnetic field, we can use the right-hand rule:

1. Identify the direction of the magnetic field: The magnetic field lines are represented by the 'x' in the diagram, indicating that the field is directed into the page.

2. Identify the velocity direction of the proton: The proton is moving towards the right in the diagram.

3. Apply the right-hand rule:

   • Point your thumb in the direction of the proton's velocity (to the right).
   • Curl your fingers in the direction of the magnetic field (into the page).

4. According to the right-hand rule, the force acting on the proton will be directed upwards, which means the proton will deflect towards the top of the page.

Therefore, the correct answer is C: deflects towards the top of the page.