The radiations having high penetrating power and not affected by electrical and magnetic field are

Which is not emitted by a radioactive substance?

Radioactive carbon dating was discovered by

$A$ radioactive nuclide $X$ decays at the rate of $1.00 \times 10^5 \ disintegration \ s^{-1} \ g^{-1}$. Radium decays at the rate of $3.70 \times 10^{10} \ disintegration \ s^{-1} \ g^{-1}$. The activity of $X$ in millicuries $g^{-1}$ $(mCi \ g^{-1})$ is

$^{14}C$ is radioactive. The activity and the disintegration product are

The radiations from a naturally occurring radio element,as seen after deflection in a magnetic field in one direction,are