Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
$m_{p}$ and $m_{n}$ are masses of proton and neutron respectively. An element of mass $M$ has $Z$ protons and $N$ neutrons then
PhysicsNuclear PhysicsMHT CETMHT CET 2007
Options:
  • A $M>Z m_{p}+N m_{n}$
  • B $M=Z m_{p}+N m_{n}$
  • C $M < Z m_{p}+N m_{n}$
  • D $M$ may be greater than less than or equal to $Z m_{p}+N m_{n}$, depending on nature of element
Solution:
2641 Upvotes Verified Answer
The correct answer is: $M < Z m_{p}+N m_{n}$
When a nucleus is formed, then the mass of nucleus is slightly less than the sum of the mass of $Z$ protons and $N$ neutrons.
ie,
$$
M < \left(Z m_{p}+N m_{n}\right)
$$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.