It is necessary ton use satellites for long distance TV transmission. Explain why?

A : It is necessary to use satellites for long distance TV transmission. R : Television signals are not properly reflected by the ionosphere therefore, reflection is effected by satellites.

(A): It is necessary to use satellites for long distance T.V transmission (R): The television signals are low frequency signals.

(a) Give three reasons why modulation of a message signal is necessary for long distance transmission. (b) Show graphically an audio singal, a carrier wave and an amplitude modulation wave.

Laser beams are used to measure long distances because

optical and radio telecopes are build on ground but X-ray astronomy is possible only from satellites or biting the earth. Explain why?

For circuits used for transporting elecrtric power, a low power factor impleis larger power loss in transmission. Explain?

(a) For circuits used for transporting electric power, a low power factor implies larger power loss in transmission. Explain. (b) power factor can oftern be improved by the use of a capacitor of appropraite capacitance in the circuit, Explain.

Space wave propagation is used in ( a ) microwave communication ( b ) satellite communication ( c ) TV transmission

Why are short waves used in long distance broadcasts?

Long distance radio broadcasts use short wave bands. Explain why?