AP EAMCET · PHYSICS · Dual Nature of Matter
If the threshold wavelength of light for photoelectric emission to take place from a metal surface is \(6250 Å\), then the work function of the metal is
(Planck's constant \(=6.6 \times 10^{-34} \mathrm{Js}\) )
- A \(3.98 \mathrm{~eV}\)
- B \(1.98 \mathrm{~eV}\)
- C \(2.98 \mathrm{~eV}\)
- D \(4.98 \mathrm{~eV}\)
Answer & Solution
Correct Answer
(B) \(1.98 \mathrm{~eV}\)
Step-by-step Solution
Detailed explanation
\( \phi = \frac{hc}{\lambda_0} \) \( \phi = \frac{6.6 \times 10^{-34} \times 3 \times 10^8}{6250 \times 10^{-10}} \) \( \phi = 3.168 \times 10^{-19} \mathrm{~J} \) \( \phi = \frac{3.168 \times 10^{-19}}{1.6 \times 10^{-19}} \mathrm{~eV} \) \( \phi = 1.98 \mathrm{~eV} \)
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
- The power utilised when a force of \((2 \hat{\mathbf{i}}+3 \hat{\mathbf{j}}+4 \hat{\mathbf{k}}) \mathrm{N}\) acts on a body for \(4 \mathrm{~s}\), producing a displacement of \((3 \hat{\mathbf{i}}+4 \hat{\mathbf{j}}+5 \hat{\mathbf{k}}) \mathrm{m}\), isAP EAMCET 2020 Easy
- Two light waves of intensities I and 21 superimpose on each other, If the path difference between the light waves reaching a point is \(12.5 \%\) of the wavelength of the light, then the resultant intensify at the point is (Both the light waves have same wavelength)AP EAMCET 2024 Medium
- The linear charge densities of two infinitely long thin and parallel wires are \(4 \mathrm{Cm}^{-1}\), \(8 \mathrm{Cm}^{-1}\) and separation between them is \(4 \mathrm{~cm}\). Then the electric field intensity at mid point on the line joining them isAP EAMCET 2017 Easy
- In Young's double slit experiment, the intensity at a point where the path difference is \(\frac{\lambda}{6}\) ( 1 being the wavelength of the light used) is \(I\). If \(I_0\) denotes the maximum intensity. \(\frac{\mathrm{I}}{\mathrm{I}_0}\), is equal toAP EAMCET 2024 Medium
- The ratio of the number of turns per unit length of two solenoids \(A\) and \(B\) is \(1: 3\) and the lengths of \(A\) and Bare in the ratio \(1: 2\). If the two solenoids have same cross sectional area, the ratio of the self inductances of the solenoids A and B isAP EAMCET 2024 Easy
- A wire of resistance ' \(R\) ' is bent in the form of a circular loop. Two points on the circle seperated by a quarter circumference are connected to a battery of emf ' \(E\) ' and negligible internal resistance. The heat generated in the wire per second isAP EAMCET 2025 Medium
More PYQs from AP EAMCET
- The equilibrium constant \(\left(K_C\right)\) for the following equilibrium
\(2 \mathrm{SO}_2(g)+\mathrm{O}_2(g) \rightleftharpoons 2 \mathrm{SO}_3(g)\)
at \(563 \mathrm{~K}\) is 100 . At equilibrium, the number of moles of \(\mathrm{SO}_3\) in the 10 litre flask is twice the number of moles of \(\mathrm{SO}_2\), then the number of moles of oxygen isAP EAMCET 2017 Medium - A non-volatile solute is dissolved in water. The \(\Delta T_b\) of resultant solution is 0.052 K . What is the freezing point of the solution (in K)?
( \(\mathrm{K}_{\mathrm{b}}\) of water \(=0.52 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1} ; \mathrm{K}_{\mathrm{f}}\) of water \(=1.86 \mathrm{~K} \mathrm{~kg}\) \(\mathrm{mol}^{-1}\), Freezing point of water \(=273 \mathrm{~K}\) )AP EAMCET 2024 Easy - The correct order of bond angles of the following is
\(\begin{array}{cccc}\mathrm{H}_2 \mathrm{O} & \mathrm{NH}_3 & \mathrm{CH}_4 & \mathrm{SO}_2 \\ \text { I } & \text { II } & \text { III } & \text { IV }\end{array}\)AP EAMCET 2023 Medium - Aball is projected from a point with a speed \(V_0\) at certain angle with the horizontal. From the same point and at the same instant, a person starts running with a constant speed \(0.5 \mathrm{~V}_0\) to catch the ball. If the person catches the ball after some time, then the angle of projection of the ball isAP EAMCET 2025 Medium
- In Young's double slit experiment, if the distance between the slits is increased to 3 times initial distance, then the ratio of initial and final fringe widths isAP EAMCET 2025 Easy
- The hybridisation of metals involved in the following complexes, respectively are \(\left[\mathrm{Mn}(\mathrm{CN})_6\right]^{3-},\left[\mathrm{CoF}_6\right]^{3-}\)AP EAMCET 2022 Easy