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

An atom has a single electron. Its ground state energy is -30 eV and its first excited state energy is -8 eV . The atom is bombarded with a stream of photons, each of energy 15 eV .

Assuming the atom being in the ground state, which of the following statements is correct?

A. Atom gets excited to the first excited state and later emit photons of 22 eV

B. Atom absorbs energy continuously until 22 eV is accumulated and then gets excited

C. Atom will not get excited, and the transmitted light will have the same frequency as the incident light

D. Atom will absorb the photon and re-emit a photon of lower energy

A

A

B

B

C

D

D

C

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

Paramagnetic substances

A. Move from a region of strong magnetic field to weak magnetic field

B. Has susceptibility less than zero

C. Attract strongly towards external magnetic field

D. Align themselves along the directions of external magnetic field

A

B

B

D

C

C

D

A

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

A wire of length 1 m has a resistance of $20 \Omega$ at $0^{\circ} \mathrm{C}$. It is uniformly stretched so that its length increases by $21 \%$. Assuming the volume of the wire remains constant, the percentage change in resistance is $n \%$. Alternatively, if the wire is heated [without stretching] through a temperature of $27^{\circ} \mathrm{C}$ and if the temperature coefficient of resistance of the material of wire is $0.004 K^{-1}$, the percentage change in resistance is $m \%$. The values of $m$ and $n$ are:

A

2.08 and 1.64

B

10.8 and 46.4

C

20.8 and 16.4

D

1.08 and 4.64

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

An object is placed 25 cm in front of a fully silvered concave mirror of focal length 15 cm . A plane mirror is placed 35 cm behind the concave mirror on the side opposite to the object. The final image after reflection first from the concave mirror and then from the plane mirror is formed at:

A

37.5 cm in front of the plane mirror

B

72.5 cm behind the concave mirror

C

107.5 cm behind the concave mirror

D

37.5 cm in front of the concave mirror