A radioactive source emits three types of radiation.
a) Name the three radiations.
b) Name the radiations which are deflected by the electric field.
c) Name the radiation which is most penetrating.

(a) $\alpha \text{(Alpha),}\beta \text{(Beta) and}\gamma \text{(Gama)}$ are the three types of radiations emitted by radioactive substances.
(b) Only charged particles are deflected in electric field. Alpha particles are positively charged, beta particles are negatively charged, and gamma radiation is electrically neutral . Thus, alpha and beta radiation are deflected in electric field.
(c) Gamma radiation is the most penetrating radiation. Gamma rays are massless and have high energy, they can pass through a medium easily. Hence, they have high penetrating power.