# basic important questions for BSNL TTA exam

1. The Shortest Distance Between Two Points Having X-y Co-Ordinates(9,24)(12,20) Is
(A) 5
(B) 25
(C) 1
(D) 7
2. The Dot Product Of Two Unit Vectors Having Directions Opposite To Each Other Is
(A) 1
(B) 0
(C) -1
(D) Not possible
3. Which Of The Following Is Correct
(A) determinant is a square matrix
(B) determinant is a number associated to a matrix
(C) determinant is a number associated to a square matrix
(D) none of these
4. A Periodic Waveform Possessing Half Wave Symmerty Has No
(A) even harmonics
(B) sine terms
(C) cosine terms
(D) odd harmonics
5. For Transmission Of Signals,optical Fiber Uses
(A) Laser
(B) ultrasound
(C) maser
(D) infrared
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6. The Mirages Seen In A Desert Is Due To
(A) Interference
(B) Reflection
(C) diffraction
(D) Refraction
7. Diamonds Are Known For Their Spectular Brilliance. Their Brilliance Is Mainly Due To
(A) total internal reflection&nbsp;
(B) refraction
(C) diffraction
(D) Fluoresence
8. Speed Of Sound In Vaccum Is
(A) zero
(B) same as that of the speed of light
(C) same as that in air
(D) slightly faster then the speed in air
9. Thr Energy Of An Electron In The 2nd Orbit Of An Excited Hydrogen Atom Is
(A) -13.6ev
(B) -6.8ev
(C) -3.4ev
(D) -27.2ev
10. The Value Of Relative Permitivity Of Vaccum Is
(A) 1
(B) 0
(C) 8.854*10power 12
(D) Infinity
11. Two Capacitors Of 2F each Are Connected In Series To A 1v Battery.the Total Charge Supplied By The Battery To Capacitor Is
(A) 1C
(B) 2C
(C) 0.5C
(D) 0.25C
12. The Capacitance Of A Capacitor Is Not affected By The
(A) plate thickness
(B) plate area
(C) seperation between plates
(D) nature of dielectric
13. Two Resistances Of R 2R are Connected in Parallel In An Electric Circuit .the Thermal Energy Developed In R 2R in The Ratio.
(A) 1:2
(B) 2:1
(C) 1:4
(D) 4:1
14. Two electric Bulbs Of 50 W 100 W Are connected in Series To Mains.which Of The Two Bulbs Will Glow brighter
(A) 50 W
(B) 100 W
(C) both 50 W &amp; 100 W
(D) none
15. Unit Of Magnetic Flux Is
(A) weber
(B) Ampere-turn
(C) coulomb
(D) tesla