WORKSHOP CALCULATION & SCIENCE (4th Semester)

WORKSHOP CALCULATION & SCIENCE

ELECTRONIC MECHANIC (4th Semester)

Choose the correct answer. Each question carries 3 marks.

1. Modulation index for FM can be………………..unit.

a) greater than b) less than c) equal to d) zero

2. The maximum peak to peak voltage of an AM wave is 16mV and the minimum peak to peak voltage is 4mV. Calculate the modulation factor.

a) 50% b) 60% c) 30% d) 66%

3. The DC output of a power supply is 12V at no load and 11V at full load. Calculate the percentage of load regulation.

a) 83% b) 0.83% c) 9.09% d) 0.909%

4. Calculate the backup for an system UPS. Load is the usage power. Suppose we are working a PC, then the load is around 300W. Power factor varies for device to device. The average power factor is 1.4. Voltage of the battery is 12V in each battery, battery Ah used for the UPS is 7.

a) .178 hours b) .198 hours c) .188 hours d) .168 hours

5. The speed of rotating magnetic field in the stator, Ns:

a) 120F   b) 120   C)120FP d) 120P

        P            FP                           F

 6). Calculate synchronous speed of a rotating magnetic field having 2 poles.

a) 3000 b) 2000 c) 6000 d) 5000

7. Base of the octal number system is………….

a) 2 b) 7 c) 8 d) 16

8. Convert (110110)2 into decimal.

a) 55 b) 54 c) 52 d) 51

9. Convert (783)10 to hexadecimal.

a) 30E b) 3015 c) 3014 d) 30F

10. (110101)2 + (1011)2 is…………..

a) (1000001)2 b) (100001)2 c) (10000001)2 d) (100100)2

11. 9’s complement of 454 is………

a) 999 b) 454 c) 544 d) 545

12. Belt used in flour mills is-----------

a) V belt b) circular belt c) rope belt d) Flat belt

13. A.A ̅ is………

a) A b) 1 c) 0 d) ̅A

14. A force of 30N is requiredto move a body of mass 35Kg on a flat horizontal at constant velocity .find coefficient of friction (take g=10m/s²⁾?

a) 315Nb) 356N c) 355Nd) 350N

15. A horizontal force of 100N is required to slide a sledge weighing 50kgF over a flat surface. Calculate co-efficient of friction. (Take g=9.8 m/s² )

a) 0.204b) 0.24c) 0.304 d) 24

16. Rahul bought a book for Rs. 250/- and sold it for Rs. 340/-. Find his profit % or loss %?

a) 26.47% b) 36% c) 100% d) 73.53%

17. If a chair was sold for Rs. 1250/- at a loss of Rs. 220/-, find the cost price of the chair?

a) Rs. 1030/- b) Rs. 1470/- c) Rs. 1100/- d) Rs. 1300/-

18.vertical component of a force P which makes an angle α with the vertical is given by.....................

a)Fy=P Sin α b) Fy=P Cos α c) Fy=P Sec α d) Fy=P Cosec α

19. The kind of equilibrium in which the position of centre of gravity is not disturbed is called…………

a) Stable b) unstable c) neutral d) none of these

20. What is the resultant of two unlike parallel forces of 25N?

a) 50 b) 0 c) 625 d) 1

21. Two forces having magnitude 5N and 8N act at apoint at angle of 45⁰ b/w them .Find the resultant forces?

a) 11 N b) 11.04N c) 12 N d) 12.04N

22. A force equal and opposite to the resultant of the force acting on a body is called…………..

a) Equivalent force b) Equilibriant c) Equal force d) Equipotential force

23. Meera bought a scientific calculator for Rs. 850/- and sold it for Rs. 600/-. Find her profit % or loss %?

a) 70.6% b) 41.6% c) 29.4% d) 23.5%

24. The maximum value of the frictional force before the body just slides over the surface of another body is called………….

a) Static b) Limiting c) Co-efficient d) Dynamic

25. 2’s compliment of 11001100 is----------

a) 00110100 b) 00011100 c) 00101011 d) 00110010