MHT CET · Physics · Atomic Physics
If ' m ' is the mass of electron, ' V ' is its velocity, ' r ' is the radius of stationary circular orbit around a nucleus with charge 'Ze' then from Bohr's first postulate the kinetic energy of the electron is
\(\left(\mathrm{K}=1 / 4 \pi \epsilon_0\right)\)
- A \(\frac{\mathrm{Ze}^2}{2 \mathrm{r}} \mathrm{K}\)
- B \(\frac{\mathrm{Ze}^2}{2 \mathrm{r}^2} \mathrm{~K}\)
- C \(\frac{\mathrm{Ze}^2}{\mathrm{r}} \mathrm{K}\)
- D \(\frac{\mathrm{Ze}}{\mathrm{r}^2} \mathrm{~K}\)
Answer & Solution
Correct Answer
(A) \(\frac{\mathrm{Ze}^2}{2 \mathrm{r}} \mathrm{K}\)
Step-by-step Solution
Detailed explanation
\(\frac{mV^2}{r} = K \frac{Ze^2}{r^2}\) \(KE = \frac{1}{2}mV^2 = \frac{1}{2} \left( K \frac{Ze^2}{r} \right)\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- A double slit experiment is immersed in water of refractive index 1.33. The slit separations \(1 \mathrm{~mm}\) and the distance between slit and screen is \(1.33 \mathrm{~m}\). The slits are illuminated by a light of wavelength \(6300 Å\). The fringe width isMHT CET 2021 Hard
- A thin uniform rod of length ' \(L\) ' and mass ' \(M\) ' is swinging freely about a horizontal axis passing through its end. Its maximum angular speed is ' \(\omega\) '. Its centre of mass rises to a maximum height of ( \(g=\) acceleration due gravity)MHT CET 2025 Medium
- The graph shows the variation of voltage ' V ' across the plates of two capacitors \(A\) and \(B\) versus increase in charge ' \(Q\) ' stored in them. Then
MHT CET 2024 Easy - The height ' \(h\) ' above the earth's surface at which the value of acceleration due to gravity ( g ) becomes \(\left(\frac{\mathrm{g}}{3}\right)\) is ( \(\mathrm{R}=\) radius of the earth)MHT CET 2024 Easy
- A convex lens of focal length ' \(f\) ' produces a real image whose size is ' \(n\) ' times the size of an object. The distance of the object from the lens isMHT CET 2024 Easy
- The molar specific heat of an ideal gas at constant pressure and constant volume is \(C_p\) and \(C_v\) respectively. If \(R\) is the universal gas constant and the ratio of \(C_p\) to \(C_v\) is \(\gamma\) then. \(C_v=\)MHT CET 2022 Easy
More PYQs from MHT CET
- If \(x, y, \mathrm{z}\) are in A.P. and \(\tan ^{-1} x, \tan ^{-1} y\) and \(\tan ^{-1} z\) are also in A.P., thenMHT CET 2023 Medium
- The standard reduction potential for \(\mathrm{Mg}^{2+} / \mathrm{Mg}\) is \(-2.37 \mathrm{~V}\) and for \(\mathrm{Cu}^{2+} / \mathrm{Cu}\) is \(0.337\). The \(E_{\text {cell }}^{\circ}\) for the following reaction is \(\mathrm{Mg}+\mathrm{Cu}^{2+} \longrightarrow \mathrm{Mg}^{2+}+\mathrm{Cu}\)MHT CET 2009 Easy
- Which of the following reaction is used to prepare toluene from bromobenzene?MHT CET 2022 Easy
- A solid sphere rolls without slipping on an inclined plane at an angle \(\theta\). The ratio of total kinetic energy to its rotational kinetic energy isMHT CET 2023 Medium
- The population of a town increases at a rate proportional to the population at that time. If the population increases from 40 thousand to 80 thousand in 40 years, then the population in another 40 years will beMHT CET 2024 Medium
- The function \(f(x)=e^{-|x|}\) isMHT CET 2007 Hard