1
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

What is the ratio of de Broglie wavelength of an electron to that of proton if the velocity of proton is $\frac{1}{6}$ the velocity of electron?

A

603:1

B

306:1

C

1:306

D

1:603

2
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

An atom with one electron has ionization energy of 24 eV . An electron in this atom makes a transition from an excited energy level, where $\mathrm{E}=-15 \mathrm{eV}$, to the ground state. What is the wavelength of the emitted photon from this transition?

A

112 nm

B

496 nm

C

775 nm

D

138 nm

3
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

Genetic Engineering is related to the principle of

A

Amplification by population inversion

B

Digital Logic

C

Superconductivity

D

The role of DNA in heredity

4
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

A monochromatic beam of photons of intensity to $1.5 \mathrm{Wm}^{-2}$ and energy 11.2 eV is incident on a material of work function 4.8 eV . What is the maximum speed of photoelectrons emitted due to photoelectric effect if, only $0.53 \%$ of the incident photons eject photoelectrons. Given mass of electron $m=9 \times 10^{-31} \mathrm{~kg}$.

A

$1.2 \times 10^6 \mathrm{~ms}^{-1}$

B

$1.4 \times 10^6 \mathrm{~ms}^{-1}$

C

$1.5 \times 10^6 \mathrm{~ms}^{-1}$

D

$1.3 \times 10^6 \mathrm{~ms}^{-1}$