JEE Mains · Physics · STD 12 - Nuclei
- JEE Mains 2020
- Medium
- Numerical
A radioactive nucleus decays by two different processes. The half life for the first process is \(10\, s\) and that for the second is \(100 s\). the effective half life of the nucleus is close to\(.....sec\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(9\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{ T _{\text {eff }}}=\frac{1}{ T _{1}}+\frac{1}{ T _{2}}\)
\(T _{ eff }=\frac{ T _{1} T _{2}}{ T _{1}+ T _{2}}=\frac{1000}{110}=\frac{100}{11}=9.09\)
\(T _{ eff } \cong 9\)
More questions from Physics
- Given below are two statements : Statement \(I\) : When the white light passed through a prism, the red light bends lesser than yellow and violet. Statement \(II\) : The refractive indices are different for different wavelengths in dispersive medium.
In the light of the above statements, choose the correct answer from the options given below :JEE Mains 2024 Hard - An oscillating \(LC\) circuit consists of a \(75\,mH\) inductor and a \(1.2\,\mu F\) capacitor. If the maximum charge to the capacitor is \(2.7\,\mu C\). The maximum current in the circuit will be \(...........\,mA\).JEE Mains 2023 Medium
- In a Young's double slit experiment, the slits are separated by 0.2 mm. If the slits separation is increased to 0.4 mm , the percentage change of the fringe width is _______.JEE Mains 2025 Easy
- A body is moving unidirectionally under the influence of a constant Power source. Its displacement in time \(t\) is proportional to _______.JEE Mains 2024 Hard
- A steel wire of length \(3.2 m \left( Y _{ S }=2.0 \times 10^{11}\,Nm ^{-2}\right)\) and a copper wire of length \(4.4\,M\) \(\left( Y _{ C }=1.1 \times 10^{11}\,Nm ^{-2}\right)\), both of radius \(1.4\,mm\) are connected end to end. When stretched by a load, the net elongation is found to be \(1.4\,mm\). The load applied, in Newton, will be. (Given \(\pi=\frac{22}{7}\))JEE Mains 2022 Hard
- Shown in the figure is a hollow icecream cone (it is open at the top). If its mass is \(M,\) radius of its top, \(R\) and height, \(H\), then its moment of inertia about its axis is
JEE Mains 2020 Hard
More PYQs from JEE Mains
- The electric field intensity produced by the radiation coming from a \(100\, W\) bulb at a distance of \(3\, m\) is \(E\). The electric field intensity produced by the radiation coming from \(60\, W\) at the same distance is \(\sqrt{\frac{x}{5}} E\). Where the value of \(x=......... .\)JEE Mains 2021 Hard
- A wire of resistance \(R\) and length \(L\) is cut into 5 equal parts. If these parts are joined parallely, then resultant resistance will be _______.JEE Mains 2024 Medium