The energy equivalent of one atomic mass unit is:

A radioactive element has half-life period 800 yr. After 6400 yr what amount will remain?

In the nucleus of ₁₁Na²³, the number of protons, neutrons and electrons are

If the binding energy per nucleon in ₃Li⁷ and ₂He⁴ nuclei are respectively 5.60 MeV and 7.06 MeV, then the energy of proton in the reaction ₃Li⁷+ p → 2 ₂He⁴ is

The nucleus ₄₈Cd¹¹⁵, after two successive β-decay will give

The ratio of the radii of the nuclei ₁₃Al²⁷ and ₅₂Te¹²⁵ is approximately 

Curie is a unit of

The nucleus ₆C¹² absorbs an energetic neutron and emits a beta particle ( β ).  The resulting nucleus is

A radioactive sample with a half-life of 1 month has the label: ‘Activity = 2 microcurie on 1 – 8 – 1991’.  What would be its activity two months earlier?

Solar energy is due to