A point charge q is placed at the center of a cube of side L. The total electric flux passing through any three faces of this cube is:

A non-polar dielectric material is placed in an external electric field. Choose the correct statement(s) from the following:
(A) There will be no change in the positions of positive and negative charges inside the dielectric.
(B) The positive charges of molecules will shift opposite to the direction of the electric field.
(C) The negative charges of molecules will shift in the direction of the electric field.
(D) The positive charges of the molecules will shift in the direction of the field and negative charges of the molecules will shift opposite to the field.
Choose the correct answer from the options given below:

The wavelength of radiation emitted, when \( \text{He}^{+} \) makes a transition from the state n = 3 to the state n = 2 will be :
(Take Rydberg constant \( R = 1.097 \times 10^{7} \text{ m}^{-1} \))

A parallel plate capacitor with air between the plates has a capacitance of 9 pF. What will be the capacitance if the distance between the plates is reduced to half and the space between the plates is filled with a dielectric of dielectric constant 7?

A concave mirror has radius of curvature 2 m. Light from a distance star is incident on the mirror. The distance of the image of the star from the mirror is :

A Convex mirror produces the magnification \( \frac{1}{3} \) and \( \frac{1}{4} \) when the object is placed at the points P and Q in front of the mirror.

In the (i) absence of electric field, and in the (ii) presence of electric field, the paths of electrons between successive collisions with the positive ions of the metal, are

The magnitude of a magnetic force on a current carrying conductor is given by :

Read the passage below and answer the question:
The accumulation of molecular species at the surface rather than in the bulk of a solid or liquid is termed as adsorption. There are two types of adsorption. In physisorption, attractive forces are mainly Van der Waals while in chemical adsorption adsorbate is held with chemical bonds adsorbent. Adsorption increases with increase in pressure and decreases as temperature is increased.
Which of the following is not characteristic of chemical adsorption?

Sickle-cell anemia is caused due to:

The value of \(\tan ^2\left(\sec ^{-1} 2\right)+\cot ^2\left(\operatorname{cosec}^{-1} 3\right)\) in equal to

Observe the given figure and answer the question.


Which one of the following is not shown in the above figures?

Which of the following techniques are used for early diagnosis of diseases?
(A). Urine analysis
(B). PCR
(C). ELISA
(D). Recombinant DNA technology (RDT)
Choose the correct answer from the options given below: