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

A singer, during his performance, stands on the edge of a circular turntable, and begins to walk along its edge with a speed of $1.5 \mathrm{~ms}^{-1}$ relative to the ground. The turn table is mounted on a frictionless vertical axle. Its radius R =3m and its moment of inertia about the axle is $150 \mathrm{~kg} \mathrm{~m}^2$. It is initially at rest. If the mass of the singer is 75 kg , the time taken by the man to complete one revolution is:

A

12.57 s

B

8.56 s

C

6.28 s

D

20.5 s

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

A pith ball of mass ' $m$ ' gram and charge ' $Q$ ' is suspended using a mass less silk thread near a large charged conducting metal sheet of area ' $A$ ' and surface charged density ' $\sigma$ '. If the silk thread makes an angle $\Theta$ with the metal sheet, then:

A

$\tan \theta \propto \sigma$

B

$\tan \theta \propto A$

C

$\tan \theta \propto m g$

D

$\tan \theta \propto \frac{1}{\sigma}$

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

The material selected for making a permanent magnet should have:

A

High coercivity, low permeability and high retentivity

B

Low coercivity, low permeability and low retentivity

C

Low coercivity, low permeability and high retentivity

D

High coercivity, high permeability and high retentivity

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

Calculate the vapour pressure that can help the formation of a spherical droplet of water of radius $6.25 \times 10^{-5} \mathrm{~m}$ at $22^{\circ} \mathrm{C}$. Given: The surface tension of water at the given temperature is $7.28 \times 10^{-2} \mathrm{Nm}^{-1}$.

A

$1.01 \times 10^5 \mathrm{~Pa}$

B

$2.33 \times 10^3 \mathrm{~Pa}$

C

$8.81 \times 10^3 \mathrm{~Pa}$

D

$6.64 \times 10^4 \mathrm{~Pa}$