CBSE 12th Physics Marking Scheme 2021 is available here for download along with latest CBSE 12th Physics Sample Paper 2021. Download now and prepare for CBSE Class 12 Physics board exam 2021.

Created On: Nov 5, 2020 10:26 IST
CBSE Class 12 Physics Marking Scheme 2021

CBSE 12th Physics Marking Scheme 2021 is available here for download along with latest CBSE 12th Physics Sample Paper 2021. These resources are important for the preparation of the upcoming CBSE 12th Physics board exam 2021. Links to download these resources are given at the end of this article.

CBSE Class 12 Physics Marking Scheme 2021:

1. Name the physical quantity having unit J/T.

Magnetic dipole moment.        [1]

2. Mention one use of part of the electromagnetic spectrum to which a wavelength of 21 cm (emitted by hydrogen in interstellar space) belongs.

Any one use of microwaves.        [1]

OR

Give the ratio of velocity of the two light waves of wavelengths 4000Å and 8000Å travelling in vacuum.

1:1.        [1]

3. An electron with charge -e and mass m travels at a speed v in a plane perpendicular to a magnetic field of magnitude B. The electron follows a circular path of radius R. In a time, t, the electron travels halfway around the circle. What is the amount of work done by the magnetic field?

Zero.        [1]

4. A solenoid with N loops of wire tightly wrapped around an iron-core is carrying an electric current I. If the current through this solenoid is reduced to half, then what change would you expect in inductance L of the solenoid.

Remains the same.        [1]

OR

An alternating current from a source is given by i=10sin314t.  What is the effective value of current and frequency of source?

7.707A, 50Hz         [½, ½]

5. What is the value of angular momentum of the electron in the second orbit of Bohr’s model of hydrogen atom?

h/2π.        [1]

6. In a photoelectric experiment, the potential required to stop the ejection of electrons from cathode is 4V. What is the value of maximum kinetic energy of emitted Photoelectrons?

4eV.         [1]

7. In decay of free neutron, name the elementary particle emitted along with proton and electron in nuclear reaction.

Antineutrino.        [1]

OR

In the following nuclear reaction, Identify unknown labelled X.

22Na11 + X ➔ ve

Electron.        [1]

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For the rest of the questions and answers, download the CBSE Class 12 Physics Marking Scheme 2021 & CBSE Class 12 Physics Sample Paper 2021 from the links given below