A potential difference of 1.2 × 10³ V is applied between a pair of horizontal metal plates in a vacuum, as shown in Fig. 3.1. [Figure 3.1] The separation of the plates is 3.6cm. The electric field between the plates is uniform. A particle of mass 5.9 × 10⁻⁶kg and charge –4.2 × 10⁻⁹C enters the field at point X with a horizontal velocity of 0.75ms⁻¹ along a line midway between the two plates. The particle is deflected by the field and hits the top plate at point Y.

1. (a)(i)a gravitational field[1]
2. (a)(ii)an electric field.[1]
3. (b)(i)Calculate the magnitude of the electric force acting on the particle in the field.[3]
4. (b)(ii)By considering the resultant vertical force acting on the particle, show that the acceleration of the particle in the electric and gravitational fields is 14ms⁻².[4]
5. (b)(iii) 1.the time taken for the particle to move from X to Y[2]
6. (b)(iii) 2.the distance p of point Y from the left-hand edge of the top plate.[1]

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