Physics · 2022
JEE Main · 28 July 2022, Shift 1 · Q52
A freshly prepared radioactive source of half life 2 hours 30 minutes emits radiation which is 64 times the permissible safe level. The minimum time,…
A freshly prepared radioactive source of half life $\displaystyle 2$ hours $\displaystyle 30$ minutes emits radiation which is $\displaystyle 64$ times the permissible safe level. The minimum time, after which it would be possible to work safely with source, will be \_\_\_\_ hours.
Official answer
15
More from Atoms and Nuclei
- Energy released when two deuterons (_1 H^2) fuse to form a helium nucleus (_2 He^4) is: (Given: Binding energy per nucleon of _1 H^2=1.1 MeV and…2025
- Assuming the validity of Bohr's atomic model for hydrogen like ions the radius of Li^++ ion in its ground state is given by 1/X a_0, where X= ____.…2025
- A hydrogen atom in its first excited state absorbs a photon of energy x × 10^-2 eV and excited to a higher energy state where the potential energy of…2022
- In the hydrogen atom, the electron makes a transition from the higher orbit (i) to a lower orbit (f). The ratio of the radius of the orbits in given…2026
- In a nuclear fission reaction of an isotope of mass M, three similar daughter nuclei of same mass are formed. The speed of a daughter nuclei in terms…2024
- Experimentally it is found that 12.8 eV energy is required to separate a hydrogen atom into a proton and an electron. So the orbital radius of the…2023
- There are 10^10 radioactive nuclei in a given radioactive element. Its half-life time is 1 minute. How many nuclei will remain after 30 seconds?…2021
- Consider the following statements: A. Atoms of each element emit characteristics spectrum. B. According to Bohr's Postulate, an electron in a…2021
JEE Main 2022 Physics question, with the answer from NTA’s final answer key. Where our answers come from.