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

If a clear liquid has a refractive index of 1.45 and a transparent solid has a refractive index of 2.9 , then for total internal reflection to occur at the interface between the two media; which of the following is correct?

A. The ray must travel from transparent solid to liquid at an angle of $15^{\circ}$

B. The ray must travel from liquid to transparent solid at an angle of $45^{\circ}$

C. The ray must travel from transparent solid to liquid at an angle of $30^{\circ}$

D. The ray must travel from liquid to transparent solid at an angle of $60^{\circ}$

A

B

B

C

C

D

D

A

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

Two deuterons are fused to form one alpha particle. If binding energy per nucleon of deuterium is 1.05 MeV and that of alpha particle is 7 MeV , what is the energy released in the formation of one alpha particle from the fusing of two deuterons?

A

24.8 MeV

B

23.8 MeV

C

26.8 MeV

D

28.3 MeV

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

If wattless current flows in an AC circuit, then the circuit is:

A. LR circuit

B. Purely capacitive circuit

C. Purely resistive circuit

D. LCR circuit

A

B

B

C

C

D

D

A

4
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

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