Two parallel metal plates in a vacuum are separated by a distance of 15mm, as shown in Fig. 6.1. A uniform electric field is produced between the plates by applying a potential difference between them. A particle of mass 1.7 × 10⁻²⁷ kg and charge +1.6 × 10⁻¹⁹C is initially at rest at point A on one plate. The particle is moved by the electric field to point B on the other plate. The particle reaches point B with kinetic energy 2.4 × 10⁻¹⁶ J. [Figure 6.1]

1. (a)Define electric field strength.[1]
2. (b)Two parallel metal plates in a vacuum are separated by a distance of 15mm, as shown in Fig. 6.1. A uniform electric field is produced between the plates by applying a potential difference between them. A particle of mass 1.7 × 10⁻²⁷ kg and charge +1.6 × 10⁻¹⁹C is initially at rest at point A on one plate. The particle is moved by the electric field to point B on the other plate. The particle reaches point B with kinetic energy 2.4 × 10⁻¹⁶ J.
3. (b)(i)Calculate the speed of the particle at point B.[2]
4. (b)(ii)State the work done by the electric field to move the particle from A to B.[1]
5. (b)(iii)Use your answer in (ii) to determine the force on the particle.[2]
6. (b)(iv)Determine the potential difference between the plates.[3]
7. (b)(v)On Fig. 6.2, sketch a graph to show the variation of the kinetic energy of the particle with the distance x from point A along the line AB. Numerical values for the kinetic energy are not required. [Figure 6.2][1]

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