This chapter is currently out of syllabus
1
JEE Main 2021 (Online) 25th July Evening Shift
Numerical
+4
-1
Out of Syllabus
A message signal of frequency 20 kHz and peak voltage of 20 volt is used to modulate a carrier wave of frequency 1 MHz and peak voltage of 20 volt. The modulation index will be :
2
JEE Main 2021 (Online) 20th July Morning Shift
Numerical
+4
-1
Out of Syllabus
A carrier wave Vc(t) = 160 sin(2$$\pi$$ $$\times$$ 106t) volts is made to vary between Vmax = 200 V and Vmin = 120 V by a message
signal Vm(t) = Am sin(2$$\pi$$ $$\times$$ 103t) volts. The peak voltage Am of the modulating signal is ___________.
3
JEE Main 2021 (Online) 18th March Evening Shift
Numerical
+4
-1
Out of Syllabus
A TV transmission tower antenna is at a height of 20 m. Suppose that the receiving antenna is at.

(i) ground level

(ii) a height of 5 m.

The increase in antenna range in case (ii) relative to case (i) is n%.

The value of n, to the nearest integer, is ___________.
4
JEE Main 2021 (Online) 17th March Morning Shift
Numerical
+4
-1
Out of Syllabus
For VHF signal broadcasting, ___________ km2 of maximum service area will be covered by an antenna tower of height 30 m, if the receiving antenna is placed at ground. Let radius of the earth be 6400 km. (Round off to the Nearest Integer) (Take $$\pi$$ as 3.14)