MCQ
Energy of photon whose frequency is ${10^{12}}MHz,$ will be
- A$4.14 \times {10^3}keV$
- B$4.14 \times {10^2}eV$
- C$4.14 \times {10^3}MeV$
- ✓$4.14 \times {10^3}eV$
✓
Answer
Correct option: D.
$4.14 \times {10^3}eV$
d
(d) $E(eV) = \frac{{h\nu }}{e} = \frac{{6.0 \times {{10}^{ - 34}} \times {{10}^{12}} \times {{10}^6}}}{{1.6 \times {{10}^{ - 19}}}}$$ = 4.14 \times {10^3}eV$.
(d) $E(eV) = \frac{{h\nu }}{e} = \frac{{6.0 \times {{10}^{ - 34}} \times {{10}^{12}} \times {{10}^6}}}{{1.6 \times {{10}^{ - 19}}}}$$ = 4.14 \times {10^3}eV$.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A vessel contains $110\, g$ of water. The heat capacity of the vessel is equal to $10\, g$ of water. The initial temperature of water in vessel is $10°C.$ If $220\, g$ of hot water at $70°C$ is poured in the vessel, the final temperature neglecting radiation loss, will be........ $^oC$
→If three helium nuclei combine to form a carbon nucleus then the energy released in this reaction is $\times 10^{-2} \mathrm{MeV}$. (Given $1 \mathrm{u}=931 \mathrm{MeV} / \mathrm{c}^2$, atomic mass of helium $=4.002603 \mathrm{u}$ )
→Two radioactive materials $X_1$ and $X_2$ contain same number of nuclei. If $6\,\lambda {s^{ - 1}}$ and $4\,\lambda {s^{ - 1}}$ are the decay constants of $X_1$ and $X_2$ respectively the ratio of number of nuclei, undecayed of $X_1$ to that of $X_2$ will be $\left( {\frac{1}{e}} \right)$ after a time
→The figure shows an experimental plot for discharging of a capacitor in an $R-C$ circuit. The time constant $\tau$ of this circuit lies between
→An optical bench has $1.5 m$ long scale having four equal divisions in each $cm$. While measuring the focal length of a convex lens, the lens is kept at $75 cm$ mark of the scale and the object pin is kept at $45 cm$ mark. The image of the object pin on the other side of the lens overlaps with image pin that is kept at $135 cm$ mark. In this experiment, the percentage error in the measurement of the focal length of the lens is. . . . .
→A spherical portion has been removed from a solid sphere having a charge distributed uniformly in its volume in the figure. The electric field inside the emptied space is
Given below are two statements : one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$,
→Assertion $(A)$ :When a fire cracker (rocket) explodes in mid air, its fragments fly in such a way that they continue moving in the same path, which the fire cracker would have followed, had it not exploded
Reason $(R)$:Explosion of cracker (rocket) occurs due to internal forces only and no external force acts for this explosion.
In the light of the above statements, choose the most appropriate answer from the options given below :
A person walks $25.0^{\circ}$ north of east for $3.18 \,km$. How far would she have to walk due north and then due east to arrive at the same location?
→A long straight wire carries a current of $35\; A$. What is the magnitude of the field $B$ at a point $20\; cm$ from the wire?
→In an insulator, the forbidden energy gap between the valence band and conduction band is of the order of