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COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0
COMEDK 2026 Morning Shift Physics - Semiconductor Devices and Logic Gates Question 4 English

In the circuit given, the reverse breakdown voltage of the Zener diode is 4.8 V . The current through the Zener and the power dissipation in Zener is:

A

$22.4 \mathrm{~mA} ; 107.52 \mathrm{~mW}$

B

$2.88 \mathrm{~mA} ; 13.82 \mathrm{~mW}$

C

$28.8 \mathrm{~mA} ; 138.24 \mathrm{~mW}$

D

$12.4 \mathrm{~mA} ; 97.52 \mathrm{~mW}$

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

In a Young's double slit experiment, the slits are separated by 0.5 mm . Fringes are obtained on a screen which is placed at distance 1 m away from the slits. When the screen is moved 7 cm farther away, the fringe width changes by $63 \mu \mathrm{~m}$. The wavelength of light used in the experiment will be:

A

$4.5 \times 10^{-6} \mathrm{~m}$

B

$4.5 \times 10^{-7} \mathrm{~m}$

C

$0.5 \times 10^{-9} \mathrm{~m}$

D

$0.5 \times 10^{-7} \mathrm{~m}$

3
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

4
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