An element _ZS^A decays to ₈₅R²²² after emitting 2 α particles and 1 β particle. Find the atomic number and atomic mass of the element S.

A radioactive substance is oxidized. Will there be any change in the nature of it's radioactivity? Give a reason for your answer.

Which coil of a step up transformer is made thicker and why?

A stone of mass 'm' is rotated in a circular path with a uniform speed by tying a strong string with the help of your hand. Answer the following questions:

(i) Is the stone moving with a uniform or variable speed?

(ii) Is the stone moving with a uniform acceleration? In which direction does the acceleration act?

(iii) What kind of force acts on the hand and state it's direction?