NBSE Class 10 Question Paper 2021 for Electronics and Hardware

Total number of printed pages : 2 NB-T/E&H(V) 2021 Electronics & Hardware (Vocational) Total marks : 50 Time : 2 hours General instructions : i) Approximately 15 minutes is allotted to read the question paper and revise the answers. ii) All questions are compulsory except Q. nos.18 to 23 where general option is given. iii) The question paper consists of 23 questions. iv) Marks allocated to every question are indicated against it. N.B: Check that all pages of the question paper are complete as indicated on the top left side. 1. Choose the correct answer from the given alternatives: 10x1=10 i. The heating element is made from (a) Iron (b) Copper (c) Nichrome (d) Nickel ii. It is an equipment used for finding out faults in electric bell. (a) Series test lamp (b) Parallel test lamp (c) Tester (d) Multimeter iii. The core of a transformer is made of (a) Copper (b) Silicon (c) Silicon steel (d) Aluminium iv. A fully charged lead acid battery cell has a specific gravity of (a) 0.25 (b) 0.5 (c) 1.15 (d) 1.25 v. Bridge rectifier circuit converts (a) AC to AC supply (b) DC to DC supply (c) AC to DC supply (d) DC to AC supply vi. The rating of MCB is normally (a) 0.2 to 30 Amp (b) 0.2 to 60 Amp (c) 0.6 to 30 Amp (d) 0.6 to 60 Amp vii. Which of the following is a type of non formal greeting? (a) Hello (b) Good morning (c) What’s up? (d) Hi viii. Dressing and grooming are important because they help us to look (a) smart (b) intelligent (c) wiser (d) comfortable ix. To connect to the internet, the computer has to be connected to the (a) Internet Society (b) Internet Architecture (c) Internet Service Provider (d) Large Area Network x. What does conservation of energy mean? (a) Using energy efficiently (b) Banning the use of energy (c) Promoting power plants (d) Planting more trees

-2- NB-T/E&H(V) Answer the following questions in one word or one sentence: 2. What is immersion heater? 1 3. Which type of switch is used to operate the electric bell? 1 4. What is full wave rectifier? 1 5. What is an inverter? 1 6. What is an emergency light? 1 7. What is CFL? 1 8. What is an introduction? 1 9. What is internet? 1 Answer the following questions in 20-50 words: 10. Draw the circuit diagram of electric bell. 2 11. Write any two advantages of LED. 2 12. What is step-up transformer? 2 13. Name any two applications of DC power supply. 2 14. Write two uses of multimeter. 2 15. Write two advantages of solar cell. 2 16. Mention any two points of importance about personal hygiene. 2 17. Write any two characteristics of entrepreneurship. 2 Answer any four from the following questions in 60-100 words: 18. Explain the working principle of electric geyser. Write one application. 3+1=4 19. What is an auto-transformer? Explain the working of auto-transformer. 1+3=4 20. Explain the working principle of emergency light. Draw its block diagram. 2+2=4 21. Describe the working principles of single phase motors. 4 22. Explain any four types of wires. 4 23. Briefly explain the short circuit test of induction cooker or hot plate with diagram. 2+2=4 ******************************************