INDIA EXAMINATIONS: CBSE PORTAL : “CBSE Class-12 Exam 2020 : Question Paper (Electrical Machines)” plus 5 more

Friday, August 21, 2020

CBSE PORTAL : “CBSE Class-12 Exam 2020 : Question Paper (Electrical Machines)” plus 5 more

CBSE Class-12 Exam 2020 : Question Paper (Electrical Machines)
CBSE Class-12 Exam 2020 : Question Paper (Electrical Appliances)
CBSE Class-10 Exam 2020 : Question Paper (Front Office Operations)
CBSE Class-10 Exam 2020 : Question Paper (French)
(Download) CBSE Class-10 Sample Paper And Marking Scheme 2019-20: (Introduction to Tourism)
(Download) CBSE Class-12 Sample Paper 2019-20 : Mechanical Engineering

CBSE Class-12 Exam 2020 : Question Paper (Electrical Machines)

Posted: 21 Aug 2020 02:53 AM PDT

CBSE Class-12 Exam 2020 : Question Paper (Electrical Machines)

Subject :-Electrical Machines
Class : XII
Year : 2020

SECTION A

PART I

Attempt any ten questions. 1x10=10

1. Iron core of a power transformer is laminated 1
(A) To reduce hysteresis loss
(B) To reduce eddy current loss
(C) To reduce copper loss
(D) Due to (A) and (B) above

2. In a transformer, the following winding has more cross-sectional area : 1
(A) Primary winding
(B) Secondary winding
(C) High voltage winding
(D) Low voltage winding

3. Cross-section of the iron core of a power transformer is approximately circular. This is done because 1
(A) It is easy to assemble a circular core.
(B) It is easy to make a circular coil.
(C) Electromagnetic forces tend to make the coil circular.
(D) Of all of the above reasons

4. If the field circuit of a D.C. series motor gets opened on a small load then 1
(A) motor will pick up very high speed.
(B) motor will slow down.
(C) motor will stop.
(D) motor will run normally.

5. Iron losses in a D.C. machine take place in 1
(A) Yoke
(B) Armature core only
(C) Yoke and armature
(D) None of the above

6. Losses which do not occur in a transformer but do occur in rotating electrical machines are 1
(A) hysteresis and eddy current losses
(B) friction and windage losses
(C) copper losses
(D) magnetic losses

7. In rush current to motor at starting is mainly reduced 1
(A) To save the motor from thermal damage
(B) To avoid starting shocks to the rotor of the motor
(C) To avoid voltage drop in the line
(D) Due to none of the above

8. A shaded pole motor does not possess 1
(A) Commutator
(B) Centrifugal switch
(C) Capacitor
(D) All of the above

9. Burning out of motor winding is due to 1
(A) Open circuiting of capacitor
(B) Change in capacitor value
(C) Short circuited capacitor
(D) None of the above

10. Starting capacitor of a FHP single-phase motor will have a capacitance of about 1
(A) 12 ⁰F
(B) 40 ⁰F
(C) 300 ⁰F
(D) 1000 ⁰F

11. An alloy of 60% lead and 40% tin is called 1
(A) Hard solder
(B) Soft solder
(C) Bronze
(D) None of the above

12. Melting point of a soft solder may be 1
(A) below 100⁰ C
(B) between 190⁰ C and 250⁰ C
(C) 600⁰ C
(D) None of the above

PART II

Attempt any five questions. 2x5=10

13. What are the various applications of voltage and current transformers ? 2
14. Why can a transformer not work on D.C. ? Write in brief. 2
15. What is armature reaction in D.C. motors ? 2
16. What is the function of poles in D.C. motors ? 2
17. Why is a D.C. motor not started without a starter ? 2
18. What are the various applications of a shaded pole motor ? 2
19. What are the various techniques used for soldering ? 2

PART III

Attempt any five questions. 3x5=15

20. Explain the construction of a core type transformer with the help of a neat sketch. 3
21. With the help of a neat sketch, explain the field control method of speed control of D.C. shunt motor. 3
22. Draw circuit diagram of a 3-point starter used in D.C. motors and label its parts. 3
23. What is a repulsion start motor ? What are its applications ? 3
24. Write the names of various starters used in 3-phase induction motors. Which horse power motors are these used for ? 3
25. What are the various applications of different single-phase motors ? 3
26. How can faults in a single-phase motor be found ? Write the step-by-step procedure ?

SECTION B

Attempt any one question. 5x1=5

27. Describe with a sketch, the construction of a universal motor. Write its working principle and uses. 5
28. What are the various methods of soldering ? What are the various components of solder and their proportion ? 5

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CBSE Board Class-XII

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सीबीएसई बोर्ड कक्षा-12

CBSE Class-12 Exam 2020 : Question Paper (Electrical Appliances)

Posted: 21 Aug 2020 02:43 AM PDT

CBSE Class-12 Exam 2020 : Question Paper (Electrical Appliances)

Subject :-Electrical Appliances
Class : XII
Year : 2020

SECTION A

PART I

Answer any ten questions : 1x10=10

1. Fault in electric iron may be 1
(A) Earth fault only
(B) Short circuit fault only
(C) Open circuit fault only
(D) All of the above faults

2. Which of the following is generally used in a hot plate ? 1
(A) Rotary switch
(B) Timer
(C) Thermostat
(D) None of the above

3. Nichrome strip wound over a triangular mica plate type heating element is used in 1
(A) Automatic electric kettle
(B) Ordinary electric kettle
(C) Both (A) and (B)
(D) None of the above

4. Exhaust fan is used in 1
(A) A washroom
(B) A desert cooler
(C) A room cooler
(D) Both (A) and (B)

5. Processes like Soak, Wash, Rinse and Spin can be performed by 1
(A) Ordinary washing machine
(B) Semi-automatic washing machine
(C) Fully automatic washing machine
(D) None of the above

6. Thermostat control is used in 1
(A) Ordinary washing machine
(B) Automatic washing machine
(C) Both (A) and (B)
(D) None of the above

7. The motor generally used in domestic electric washing machine is 1
(A) Capacitor start capacitor run motor
(B) Reluctance motor
(C) Split-Phase motor
(D) None of the above

8. Defect in curler may be due to 1
(A) Defect in motor
(B) Defect in heating element
(C) Defect in cord
(D) Both (B) and (C)

9. The starting winding of a single-phase induction motor is placed in a 1
(A) Rotor
(B) Stator
(C) Field
(D) None of the above

10. Defect in motor may be due to 1
(A) Open circuit in the winding
(B) Worn bearing
(C) Locking at air gap
(D) All of the above

11. Universal motor is generally used in 1
(A) Clothes washing machine
(B) Exhaust fan
(C) Both (A) and (B)
(D) None of the above

12. When electric equipments are lifted manually, the person should have 1
(A) Firm footing
(B) Straight back
(C) Chin inward
(D) All of the above

PART II

Answer any five questions. 2x5=10

13. Describe in brief the functions of an O.T.G. 2
14. Describe in brief the construction of a geyser. 2
15. Describe the procedure involved in the repair of a defective heat convector. 2
16. Describe the testing and repairing procedure of a defective blender. 2
17. Describe the installation procedure of a desert cooler. 2
18. Describe the common faults and their causes in a vacuum cleaner. 2
19. Give a brief description of the equipment required to handle heavy electrical machines. 2

PART III

Answer any five questions. 3x5=15

20. What defects can be found in a bowl type room heater, and how can they be removed ? 3
21. Describe the procedure of testing and repairing of a defective hot plate. 3
22. Describe the common defects and their causes in an ordinary electric toaster. 3
23. Explain the construction and working of an ordinary electric washing machine. 3
24. Draw the circuit diagram of a manual voltage stabiliser and briefly describe its working. 3
25. Which type of motor is used in a small electric drill machine ? Describe its special features. 3
26. What precautions are to be taken to avoid an electric shock ? Explain. 3

SECTION B

Answer any one question. 5x1=5

27. Explain the defects in a blower type room heater, and how they can be removed. 5
28. Describe in detail the construction of a pedestal fan and the motor used
in it, and also give its uses.

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CBSE Board Class-XII

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सीबीएसई बोर्ड कक्षा-12

सीबीएसई बोर्ड पेपर

Papers

Electrical Appliances

Class-12

CBSE Class-10 Exam 2020 : Question Paper (Front Office Operations)

Posted: 21 Aug 2020 02:04 AM PDT

CBSE Class-10 Exam 2020 : Question Paper (Front Office Operations)

Subject : Front Office Operations
Time allowed : 3 hours
Maximum Marks : 80

SECTION A

(Employability Skills)

Answer any 4 questions out of the given 6 questions of 1 mark each. 14=4

1. Which of the following is a declarative sentence ? 1
(A) Take the medicine after meal.
(B) Where are my keys ?
(C) I have a headache.
(D) When is your exam ?

2. To make the letters appear bold and in italics, which buttons will you press on the keyboard with Ctrl ? 1
(A) C and B
(B) V and I
(C) B and I
(D) P and B

3. Time management can be done by 1
(A) Living in the present
(B) Keeping yourself busy
(C) Making a time table
(D) Thinking positive

4. Who is a Fabian Entrepreneur ? 1
One who
(A) is lazy
(B) does not want to change
(C) adopts innovation
(D) does not cooperate

5. How can we save our planet from air pollution ? By 1

(A) not playing loud music
(B) not using plastics
(C) buying unnecessary things
(D) using public transport

6. Neha’s parents are going to get divorced. What kind of stress may she suffer from ? 1

(A) Mental stress
(B) Financial stress
(C) Social stress
(D) Physical stress

Answer any 3 questions out of the given 5 questions of 2 marks each. 23=6

7. Give four suggestions to be a good listener during communication. 2
8. Suggest any four ways to manage stress. 2
9. Give four suggestions to maintain a computer. 2
10. Write any four advantages of entrepreneurship. 2
11. Name any four non-renewable natural resources. 2

SECTION B

(Subject Skills)

Answer any 10 questions out of the given 12 questions of 1 mark each. 110=10

12. What is the currency of Malaysia ? 1
(A) Ringgit
(B) Yen
(C) Baht
(D) Dollar

13. What is the capital of Belgium ? 1
(A) Brussels
(B) Vienna
(C) Paris
(D) Berlin

14. What is the airline code of British Airways ? 1
(A) BS
(B) BM
(C) BA
(D) FB

15. Itanagar is the capital of which State ? 1
(A) Arunachal Pradesh
(B) Andhra Pradesh
(C) Madhya Pradesh
(D) Uttar Pradesh

16. Which quality will help the front office staff to solve guest problems ? 1
(A) Punctuality
(B) Honesty
(C) Alertness
(D) Diplomacy

17. First impression of a hotel is created by their front office staff. So which quality should they possess ? 1
(A) Patience
(B) Beauty
(C) Well-groomed
(D) Active

18. Who is responsible for check-in of guests ? 1
(A) Receptionist
(B) Concierge
(C) Bell Desk
(D) Cashier

19. Secretarial services are provided by 1
(A) Concierge
(B) Travel Desk
(C) Reservations
(D) Business Centre

20. Who provides communication facilities to the guests ? 1
(A) Telephone Section
(B) Cashier
(C) Travel Desk
(D) Reception

21. Computer data is processed by the computer’s 1
(A) Files
(B) Folders
(C) CPU
(D) Hard disk

22. How many Megabytes is equal to 1 Gigabyte ? 1
(A) 1024 Megabytes
(B) 1204 Megabytes
(C) 1000 Megabytes
(D) 1042 Megabytes

23. _________ is an example of external storage of the computer. 1
(A) RAM
(B) USB
(C) ROM
(D) In-built hard disk

Answer any 4 questions out of the given 6 questions of 2 marks each. 24=8

24. Why is it important for staff to read a newspaper ? Give four reasons for this. 2
25. Franc, Euro, Riyal and Dirham are currencies of which countries ? 2
26. What four points should a receptionist keep in mind while communicating with the guests ? 2
27. Give four reasons to promote personal hygiene in front office staff. 2
28. Explain the role of a cashier in the front office department. 2
29. Mention any four functions of a Reservation Section. 2

Answer any 4 questions out of the given 6 questions of 3 marks each. 34=12

30. Mention any six grooming standards for male staff of front office. 3
31. Give six suggestions to women staff of front office to keep their nails attractive. 3
32. Why is it important for the front office staff to be physically fit ? Give three reasons. 3 3
33. Write six features of a hotel lobby. 3
34. Briefly describe any six duties performed by the Bellboy of a hotel. 3
35. State any six ways the hotel industry has been benefitted by the computers. 3

Answer any 2 questions out of the given 4 questions of 5 marks each. 52=10

36. Elaborate five advantages of using a newspaper. 5
37. Give ten instructions to the front office staff regarding their uniform. 5
38. Where is the registration desk located in a hotel ? Who is incharge of this section ? Write six important activities performed here. 5
39. Neatly draw a hierarchial chart of the front office department of a five-star hotel.

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CBSE Board Class-X

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सीबीएसई बोर्ड कक्षा-10

CBSE Class-10 Exam 2020 : Question Paper (French)

Posted: 21 Aug 2020 01:20 AM PDT

CBSE Class-10 Exam 2020 : Question Paper (French)

Subject : French
Time allowed : 3 hours
Maximum Marks : 80

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CBSE Board Class-X

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सीबीएसई बोर्ड कक्षा-10

(Download) CBSE Class-10 Sample Paper And Marking Scheme 2019-20: (Introduction to Tourism)

Posted: 20 Aug 2020 10:59 PM PDT

(Download) CBSE Class-10 Sample Paper And Marking Scheme 2019-20:

(Introduction to Tourism)

Class X (2018-19)
Time: 2 hours Max Marks: 50

SECTION –A

Fill in the blanks (1mark each).
Answer any 10 questions out of the given 12 questions:

1. Positive attitude leads to _______________ body language. (1)

2. The group of traits that makes you unique is your ________________. (1)

3. The objectives of the _____________ are to promote and develop sustainable tourism. (1)

4. Tourism increases ___________________ opportunities. (1)

5. The full form of GIT is ___________________ tour. (1)

6. ______________ can cause serious havoc with one’s travel plans. (1)

7. A travel agent also acts as a _______________ between tour operator and the tourists. (1)

8. Ticketing is one of the ______________ activities of the Travel agency. (1)

9. There are 32 world _____________ sites in India. (1)

10. Entertainment is the ___________ of many tourist journey. (1)

11. Good __________ conditions help in taking tourism activities possible and enjoyable. (1)

12. ______________ camel fair is one of the largest camel fairs in India. (1)

Very Short Questions: (2 marks each).
Answer any 5 questions out of the given 7 questions:

13. Write a short note on power of positive work attitude. (2)

14. Write the importance of attire in Travel Industry (2)

15. Define the term Attitude. (2)

16. Name the key sources of tourism information. (2)

17. Write the Topology of tourism impact. (2)

18. What do you understand by VISA ? (2)

19. What is heritage? (2)

Short Questions: (3 marks each).
Answer any 5 questions out of the given 7 questions:

20. List the principles which help us to inculcate work place etiquettes. (3)

21. Explain the term Heredity. (3)

22. “Tourism Industry is an industry where social attractiveness of personality is very important”. Explain and give examples in support of your argument. (3)

23. Define Tourism and discuss its categories. (3)

24. Name various impacts which have laid down the need of Tourism Industry. (3)

25. What do you means by Inbound Tourism? (3)

26. Why beaches are important Tourism product? (3)

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Sample Paper

Class-10

(Download) CBSE Class-12 Sample Paper 2019-20 : Mechanical Engineering

Posted: 20 Aug 2020 10:57 PM PDT

(Download) CBSE Class-12 Sample Paper 2019-20 : Mechanical Engineering

Class: XII
Mechanical Engineering-626
Sample Question Paper 2019-20

SECTION –A

Answer any 10 questions out of the given 12 questions-(1 Mark Each) Choose the correct answer

Q1 In a four stroke engine number of power stroke in two rotation of crank shaft is
a) One
b) Two
c) Three
d) Four

Q2 The friction disk is positioned between the flywheel and _______.
a) Engine
b) Crankshaft
c) Pressure plate
d) Differential

Q3 Distance travelled by the piston in moving from T.D.C. to the B.D.C is called
a) Stroke.
b) Bore.
c) Clearance volume.
d) Displacement Volume.

Q4 The velocity ratio of two pulleys connected by an open belt or crossed belt is
a) directly proportional to their diameters.
b) inversely proportional to their diameters.
c) directly proportional to the square of their diameters.
d) inversely proportional to the square of their diameters.

Q5 When two pulleys of different diameters are connected by means of an open belt drive,then the angle of contact taken into consideration should be of the
a) larger pulley.
b) smaller pulley.
c) average of two pulleys.
d) none of the mentioned.

Q6 Which gear train is used for higher velocity ratios in a small space?
a) Simple gear train
b) Compound gear train
c) Reverted gear train
d) Epicyclic gear train

Q7 The function of the following fitting is to extinguish boiler furnace fire in case of water level falling below safe level:
a) Feed check valve
b) Blow off cock
c) Safety valve
d) Fusible plug

Q8 Which of the following as referred to steam boiler is defined as mounting?
a) Safety valve
b) Economizer
c) Air pre heater
d) Feed Pump

Q9 What is the function of Blow down valve of a boiler?
a) To remove sludge
b) To build sediments
c) To remove Flue gas
d) To remove ash

Q10 Which of the following is an impulse turbine?
a) Pelton turbine
b) Francis turbine
c) Kaplan turbine
d) Propeller turbine

Q11 Kaplan turbine is:
a) A high head mixed flow turbine
b) A low head axial flow turbine
c) An outward flow reaction turbine
d) An impulse inward flow turbine

Q12 _______ restricts the crane from tipping
a) Gear
b) Indicator
c) Counterweights
d) Boom