Question

A uniform electric field of $10 N / C$ is created between two parallel charged plates (as shown in figure) An electron enters the field symmetrically between the plates with a kinetic energy $05 eV$ The length of each plate is $10 cm$ The angle $(\theta)$ of deviation of the path of electron as it comes out of the field is ___ (in degree)

Answer 1

Correct Answer: 45

1. Kinetic energy of the electron: \[ \frac{1}{2} mv^2 = 5 \, \text{eV}. \]
Convert \(5 \, \text{eV}\) to joules: \[ 5 \cdot 1.6 \times 10^{-19} = 8 \times 10^{-19} \, \text{J}. \]
Solve for \(v\): \[ v_x = \sqrt{\frac{2 \cdot 8 \times 10^{-19}}{9.1 \times 10^{-31}}}. \]
2. Vertical displacement: \[ \tan \theta = \frac{E_y}{E_x}. \]
Substituting: \[ \theta = \tan^{-1}(1) = 45^\circ. \]
Thus, the angle of deviation is 45°. The deviation of the path in a uniform electric field depends on the balance between horizontal and vertical forces on the electron.