AP EAPCET 2025 - 24th May Morning Shift | Dual Nature of Radiation Question 5 | Physics

A laser produces a beam of light of frequency $5 \times 10^{14}$ Hz with an output power of 33 mW . The average number of photons emitted by the laser per second is (Planck's constant $=6.6 \times 10^{-34} \mathrm{Js}$ )

$40 \times 10^{16}$

$10 \times 10^{16}$

$30 \times 10^{16}$

$20 \times 10^8$

AP EAPCET 2025 - 23rd May Evening Shift

MCQ (Single Correct Answer)

-0

If the de-Broglie wavelength of an electron is 2 nm , then its kinetic energy is nearly (Planck's constant $=6.6 \times 10^{-34} \mathrm{Js}$ and mass of electron $=9 \times 10^{-31} \mathrm{~kg}$ )

0.48 eV

0.68 eV

0.38 eV

0.25 eV

AP EAPCET 2025 - 23rd May Morning Shift

MCQ (Single Correct Answer)

-0

If a proton and an alpha particle are accelerated through the same potential difference, then the ratio of their de-Broglie wavelengths is

$1: 2$

$1: 4$

$2 \sqrt{2}: 1$

$1: 8$

AP EAPCET 2025 - 22nd May Evening Shift

MCQ (Single Correct Answer)

-0

If the threshold wavelength of light for photoelectric emission to take place from a metal surface is $6250 \mathop {\rm{A}}\limits^{\rm{o}}$, then the work function of the metal is (Planck's constant $=6.6 \times 10^{-34} \mathrm{Js}$ )

3.98 eV

1.98 eV

2.98 eV

4.98 eV

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