# NSO Free Sample PDF Papers for Class 12

May 20, 2023

## National Science Olympiad 2022-23 – Download free NSO Level 1 PDF Sample Papers for Class 12

Guidelines for the Candidate

1. You will get additional ten minutes to fill up information about yourself on the OMR Sheet, before the start of the exam.

2. Write your Name, School Code, Class, Roll No. and Mobile Number clearly on the OMR Sheet and do not forget to sign it. We will share your marks / result and other information related to Olympiad exams on your mobile number.

3. The Question Paper comprises sections: reasoning, subjective, achiever’s section

4. All questions are compulsory. There is no negative marking. Use of calculator is not permitted.

5. There is only ONE correct answer. Choose only ONE option for an answer.

6. To mark your choice of answers by darkening the circles on the OMR Sheet, use HB Pencil or Blue / Black ball point pen only

7. Rough work should be done in the blank space provided in this booklet.

8. Return the OMR Sheet to the invigilator at the end of the exam.

1. Choose the correct option.

Assertion – On going away from a small electric dipole, the electric field decreases.

Reason – electric field is inversely proportional to the square of the distance from an electric dipole.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. An assertion is false, and a reason is also false.

2. The angle of dip at a certain place on the earth is 60° and the magnitude of the earth’s horizontal component of magnetic field is 0.26 G. The magnetic field at the place on the earth is:

1. 0.13 G
2. 0.26 G
3. 0.52 G
4. 0.65 G

3. Choose the correct option.

Assertion – capacity of a parallel plate capacitor increases when the distance between the plates is increased.

Reason – capacitance of a capacitor is directly proportional to the distance between them.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. An assertion is false, and a reason is also false.

4. A transformer has 1500 turns in the primary coil and 1125 turns in the secondary coil. If the voltage in the primary coil is 200 V, then the voltage in the secondary coil is:

1. 100 V
2. 150 V
3. 200V
4. 250 V

5. The phenomena involved in the reflection of radio waves by ionosphere is similar to:

1. reflection of light by a plane mirror.
2. total internal reflection of light in air during a mirage.
3. dispersion of light by water molecules during the formation of a rainbow.
4. scattering of light by the particles of air.

6. Heavy, stable nuclei have more neutrons than protons. This is because of the fact that:

1. Neutrons are heavier than protons.
2. Electrostatic forces between protons are repulsive.
3. Neutrons decay into protons through beta decay.
4. Nuclear forces between neutrons are weaker than those between protons.

7. Which of the following option is/are incorrect. An audio signal of 15kHz frequency cannot be transmitted over long distances without modulation because:

1. the size of the required antenna would be at least 5 km which is not convenient.
2. the audio signal cannot be transmitted through sky waves.
3. the size of the required antenna would be at least 20 km, which is not convenient.
4. effective power transmitted would be very low, if the size of the antenna is less than 5 km.

8. Which of the following statements is not correct about an inert electrode in a cell?

1. It does not participate in the cell reaction.
2. It provides a surface either for oxidation or for reduction reactions.
3. It provides a surface for the conduction of electrons.
4. It provides a surface for redox reactions.

9. The value of the rate constant of a pseudo first order reaction is ____________.

1. depends on the concentration of reactants present in excess.
2. depends on the concentration of reactants present in small amounts.
3. is independent of the concentration of reactants.
4. depends only on temperature.

10. Match the following and choose the correct options:

1. A-ii, B-i, C-iii, D-iv
2. A-iii, B-iv, C-ii, D-i
3. A-iii, B-i, C-ii, D-iv
4. A-ii, B-iv, C-iii, D-i

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