enEnglishhiहिन्दी
JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
When radiation of wavelength \(\lambda \) is incident on a metallic surface, the stopping potential is \(4.8\) volts. If the same surface is illuminated with radiation of double the wavelength, then the stopping potential becomes \(1.6\) volts. Then the threshold wavelength for the surface is
- A \(2\lambda \)
- B \(4\lambda \)
- C \(6\lambda \)
- D \(8\lambda \)
Answer & Solution
Correct Answer
(B) \(4\lambda \)
Step-by-step Solution
Detailed explanation
(b)By using \(\frac{{hc}}{e}\left( {\frac{1}{\lambda } - \frac{1}{{{\lambda _0}}}} \right) = {V_0}\) \( \Rightarrow \frac{{hc}}{e}\left( {\frac{1}{\lambda } - \frac{1}{{{\lambda _0}}}} \right) = 4.8\)….\(.(i)\) and…
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 proton, a neutron, an electron and an \(\alpha\,-\)particle have same energy. If \(\lambda_{ p }, \lambda_{ n }, \lambda_{ e }\) and \(\lambda_{\alpha}\) are the de Broglie's wavelengths of proton, neutron, electron and \(\alpha\) particle respectively, then choose the correct relation from the followingJEE Mains 2022 Medium
- The output \((\mathrm{Y})\) of logic circuit given below is \(0\) only when :
JEE Mains 2024 Hard - For the circuit shown below, the current through the Zener diode is......\(mA\)
JEE Mains 2019 Medium - Two Carnot engines \(A\) and \(B\) are operated in series. Engine \(A\) receives heat from a reservoir at \(600\,K\) and rejects heat to a reservoir at temperature \(T\). Engine \(B\) receives; heat rejected by engine \(A\) and in turn rejects it to a reservoir at \(100\,K\). If the efficiencies of the two engines \(A\) and \(B\) are represented by \({\eta _A}\) and \({\eta _B}\) respectively, then what is the value of \(\frac{{{\eta _A}}}{{{\eta _B}}}\)JEE Mains 2018 Hard
- In hydrogen like system the ratio of coulombian force and gravitational force between an electron and a proton is in the order of _______.JEE Mains 2024 Hard
- An external pressure \(P\) is applied on a cube at \(0^o C\) so that it is equally compressed from all sides. \(K\) is the bulk modulus of the material of the cube and a is its coefficient of linear expansion. Suppose we want to bring the cube to its original size by heating. The temperature should be raised byJEE Mains 2017 Hard
More PYQs from JEE Mains
- Let the circle \(x^{2}+y^{2}=4\) intersect x-axis at the points \(A(a,0), a>0\) and \(B(b,0)\). Let \(P(2 \cos\alpha, 2 \sin\alpha), 0<\alpha<\frac{\pi}{2}\) and \(Q(2 \cos\beta, 2 \sin\beta)\) be two points such that \((\alpha-\beta)=\frac{\pi}{2}.\) Then the point of intersection of AQ and BP lies on:JEE Mains 2026 Medium
- A capillary tube made of glass of radius \(0.15\, mm\) is dipped vertically in a beaker filled with methylene iodide (surface tension \(=0.05\, Nm ^{-1},\) density \(\left.=667\, kg m ^{-3}\right)\) which rises to height \(h\) in the tube. It is observed that the two tangents drawn from liquid-glass interfaces (from opp. sides of the capillary) make an angle of \(60^{\circ}\) with one another. Then \(h\) is close to \(......m\) \(\left(g=10\, ms ^{-2}\right)\)JEE Mains 2020 Hard
- A nucleus with mass number \(184\) initially at rest emits an \(\alpha\)-particle. If the \(Q\) value of the reaction is \(5.5\, {MeV}\), calculate the kinetic energy of the \(\alpha-\) particle. (In \({MeV}\))JEE Mains 2021 Hard
- Five equal resistances are connected in a network as shown in figure. The net resistance between the points \(A\) and \(B\) is
JEE Mains 2021 Medium - The mean of a data set consisting of \(20\) observations is \(40\). If one observation \(53\) was wrongly recorded as \(33\), then the correct mean will beJEE Mains 2013 Hard
- If \(b _{ n }=\int \limits_{0}^{\frac{\pi}{2}} \frac{\cos ^{2} nx }{\sin x } dx , n \in N\), thenJEE Mains 2022 Hard