CBSE Class 12 Home Science Question Paper 2022 with Answer Key (May 25)

CBSE CLASS XII Questions

• 1.

  Which one of the following materials has magnetic susceptibility $\chi$ in the range $-1 \leq \chi < 0$?

  • Aluminium
  • Copper chloride
  • Copper
  • Nickel
  View Solution

  ---

• 2.

  A photosensitive surface is illuminated by radiations of wavelength $\lambda_{1}$, $\lambda_{2}\;(>\lambda_{1})$ and $\lambda_{3}$ one by one and photoemission is observed in each case. $\lambda_{1}$ and $\lambda_{2}$ lie in UV range and $\lambda_{3}$ in visible range. If $V_{1}$, $V_{2}$ and $V_{3}$ are stopping potentials in these cases respectively, then:

  • $V_{1} = V_{2} = V_{3}$
  • $V_{2} > V_{1} > V_{3}$
  • $V_{1} > V_{2} > V_{3}$
  • $V_{3} > V_{1} > V_{2}$
  View Solution

  ---

• 3.

  Radiation of wavelength 331 nm irradiates the following metals:

  Metal	Work Function (eV)
  Na	1.92
  K	2.15
  Ca	3.20
  Mo	4.17

  Which of the following statements is correct?

  • Only Na and K show photoelectric emission.
  • Only Mo will not show photoelectric emission.
  • All of the given metals show photoelectric emission.
  • None of them show photoelectric emission.
  View Solution

  ---

• 4.

  The equivalent mass of a photon of wavelength $100\ \text{nm}$ is:

  • $2.21\times 10^{-35}\ \text{kg}$
  • $6.63\times 10^{-33}\ \text{kg}$
  • $1.11\times 10^{-35}\ \text{kg}$
  • $3.31\times 10^{-33}\ \text{kg}$
  View Solution

  ---

• 5.

  (a) An electric field $\vec{E}$ is established across the ends of a cylindrical conductor of length $L$ and area of cross-section $A$. Discuss how electrons attain an average velocity, independent of time. Hence, obtain a relation between current in the conductor and this ‘average velocity’ of electrons.

  (b) (i) This ‘average velocity’ is found to be a few $\text{mm}\,\text{s}^{-1}$ for currents in range of a few amperes. How then is current established almost the instant a circuit is closed?

  (ii) Two copper wires having their radii in the ratio of $3:2$ are connected in series across a battery. Find the ratio of the drift velocities of the electrons in the wires.

  View Solution

  ---

• 6.

  An equiconvex lens of focal length $15$ cm is cut into two equal plano-convex halves. The focal length of each half will be:

  • $30$ cm
  • $20$ cm
  • $15$ cm
  • $7.5$ cm
  View Solution