Question

है?
What is modulation? Why is it necessary in communication system
for sending a message?
-16
किसी 20 सेमी. फोकस दूरी के उत्तल लेंस के सम्पर्क में रखे 30 सेमी. फोकस दूरी के
अवतल लेंस के संयोजन से बने संयुक्त लेंस की फोकस दूरी क्या है? क्या यह संयोजन
अभिसारी लेंस है, अथवा अपसारी?
What is the focus distance of a combined lens made by combinin
a concave lenses of 30 cm focus distance placed in contact with
convex lens of 20 cm focus distance? Whether this combination i
convergent lens or divergent?​

Answer 1

Answer:

MODULATION

Explanation:

Modulation allows us to send a signal over a bandpass frequency range. If every signal gets its own frequency range, then we can transmit multiple signals simultaneously over a single channel, all using different frequency ranges. Another reason to modulate a signal is to allow the use of a smaller antenna.