Download App

Communication — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsCommunication1 Mark
Question

Assertion : Fax is a modulating and demodulating device.

Reason     : It is necessary for exact reproduction of a document.

(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c) If assertion is true but reason is false.

(d) If assertion is false but reason is true.
✓

Answer

(d) If assertion is false but reason is true.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q [1M]" from Communication→Communication — all question types→Physics STD 12 Science question papers→Bihar Board STD 12 Science question papers→Bihar Board question paper generator→

Similar questions

If in compound microscope m1 and m2 be the linear magnification of the objective lens and eye lens respectively, then magnifying power of the compound microscope will be

(a)      

 (b)    

(c)  

(d)    
→
A body has its centre of mass at the origin. the x-coordinates of the particles:
  1. May be all positive.
  2. May be all negative.
  3. May be all non-negative.
  4. May be positive for some cases and negative in other cases.
→

In a movie hall, the distance between the projector and the screen is increased by 1% illumination on the screen is

(a) Increased by 1%

(b) Decreased by 1%

(c) Increased by 2%

(d) Decreased by 2%
→
The net charge on a condenser is:
→
According to Einstein's photoelectric equation, the graph of K.E. of the photoelectron emitted from the metal versus the frequency of the incident radiation gives a straight line graph, whose slope:
→

Two thin lenses of focal lengths 20 cm and 25 cm are placed in contact convex. The effective power of the combination is

(a) 45 dioptres

(b) 9 dioptres

(c) 1/9 dioptre

(d) 6 dioptres
→
Assume that each diode shown in the figure has a forward bias resistance of $50 \Omega$ and an infinite reverse bia resistance. The current through the $150 \Omega$ resistance is
Image
→
The measurement of an unknown resistance R is to be carried out using Wheatstones bridge (see Fig. of NCERT Book). Two students perform an experiment in two ways. The first students takes R2 = 10Ω and R1 = 5Ω. The other student takes R2 = 1000Ω and R1 = 500Ω. In the standard arm, both take R3 = 5Ω.
Both find $\text{R}=\frac{\text{R}_2}{\text{R}_1}\text{R}_3=10\Omega$ within errors.
→

Wave nature of light is verified by

(a) Interference

(b) Photoelectric effect

(c) Reflection

(d) Refraction
→

Avalanche breakdown is due to

(a) Collision of minority charge carrier

(b) Increase in depletion layer thickness

(c) Decrease in depletion layer thickness

(d) None of these
→