# CBSE Sample Papers for Class 12 Physics 2020

CBSE Sample Papers for Class 12 Physics with solutions and marking scheme in PDF format to free download. NCERT Solutions of all subjects and NCERT books in PDF form along with Previous 10 years papers of the region All India, Foreign and Delhi set 1, set 2 and set 3 with marking scheme issued by CBSE board. Click here to ask questions or give answers.

## CBSE Sample Papers for Class 12 Physics

Download CBSE Sample Papers for Class 12 Physics for the board exams. Also download main and compartment exams papers of Delhi and other CBSE issued papers to understand the CBSE pattern. Solutions of papers are also available to download in PDF form.

#### Previous Years Papers with solutions

CBSE Board Exam Papers – 2018 Compartment Exams

CBSE Board Exam Papers – 2018 Main Exams

CBSE Board Exam Papers – 2017 Compartment Exams

CBSE Board Exam Papers – 2017 Main Exams

CBSE Board Exam Papers – 2016 Main Exams

CBSE Board Exam Papers – 2015 Compartment Exams

CBSE Board Exam Papers – 2015 Main Exams

CBSE Board Exam Papers – 2014 Compartment Exams

CBSE Board Exam Papers – 2014 Main Exams

#### Important Questions from CBSE Papers – 2018

1. Draw graphs showing variation of photoelectric current with applied voltage for two incident radiations of equal frequency and different intensities. Mark the graph for the radiation of higher intensity.
2. Two electric bulbs P and Q have their resistances in the ratio of 1 : 2. They are connected in series across a battery. Find the ratio of the power dissipation in these bulbs.
3. A carrier wave of peak voltage 15 V is used to transmit a message signal. Find the peak voltage of the modulating signal in order to have a modulation index of 60%.
4. (a) Define the term ‘conductivity’ of a metallic wire. Write its SI unit.
(b) Using the concept of free electrons in a conductor, derive the expression for the conductivity of a wire in terms of number density and relaxation time. Hence obtain the relation between current density and the applied electric field E.

#### Important Questions from CBSE Papers – 2017

• A long straight current carrying wire passes normally through the centre of circular loop. If the current through the wire increases, will there be an induced emf in the loop? Justify.
• How does Ampere-Maxwell law explain the flow of current through a capacitor when it is being charged by a battery ? Write the expression for the displacement current in terms of the rate of change of electric flux.
• Define the’ distance of closest approach. An a-particle of kinetic energy ‘K’ is bombarded on a thin gold foil. The distance of the closest approach is ‘r’. What will be the distance of closest approach for an a-particle of double the kinetic energy?
• A 12 pF capacitor is connected to a 50 v battery. How much electrostatic energy is stored in the capacitor? If another capacitor of 6 pF is connected in series with it with the same battery connected across the combination, find the charge stored and potential difference across each capacitor.
• Describe the working principle of a moving coil galvanometer. Why is it necessary to use (i) a radial magnetic field and (ii) a cylindrical soft iron core in a galvanometer? Write the expression for current sensitivity of the galvanometer. Can a galvanometer as such be used for measuring the current? Explain.