Question

Why was a spherical sulphide screen used in $\alpha$-ray scattering experiment?

Answer 1

The Alpha Scattering Experiment of Rutherford

1. In this experiment, he bombarded a thin sheet of gold foil with alpha particles and studied the deflection caused to alpha particles by placing a zinc sulfide screen around the gold foil.
2. He observed that:

• Most of the alpha particles passed through the gold foil sheet without any deflection.
• Some of the alpha particles are deflected by a small angle.
• Very few alpha particles got deflected back by 180^° angle.

Spherical sulphide screen used in $\alpha$-ray scattering experiment:

1. The zinc sulphide screen aids in the detection of alpha-particles after scattering from gold foil in $\alpha$ -ray scattering experiment.
2. When alpha particles strike the zinc sulphide screen, flashes of light appear.
3. The dispersion of alpha particles was investigated using these light flashes by observing different deflection angles.
4. Hence, Zinc sulphide is employed in $\alpha$ -ray scattering experiments because of its ability to produce light flashes after colliding with an $\alpha$ particle.