Explanation:

Alpha particles

• They are doubly ionised helium nuclei having a mass equal to 6.64 × 10–27 kg and charge equal to 3.2 × l0–19 C.
• They have the highest ionising power.
• They have the least penetrating power.
• They produce fluorescence in the zinc sulphide screen.

Beta particles.

• They are negatively charged particles, having a charge equal to –1.6 × 10– 19 C and mass 9.1 × 10–31 kg.
• They have more penetration power than ?-particles.
• They have less ionising power than ?-particles.
• They affect photographic plate.

Gamma radiations

• They are electromagnetic waves, having wavelength less than 0.01 Å.
• They have a very high penetration power.
• They have a very low ionising power.
• They are not affected by electric or magnetic fields