An amplitude modulated signal is given by V(t)=10[1+0.3cos(2.2×104)]sin(5.5×105t). Here t is in seconds. The sideband frequencies (in kHz) are, [Given 
(a)
1785and 1715
(b)
892.5 and 857.5
(c)
89.25 and 85.75
(d)
178.5 and 171.5
An amplitude modulated signal is given by V(t)=10[1+0.3cos(2.2×104)]sin(5.5×105t). Here t is in seconds. The sideband frequencies (in kHz) are, [Given
(a)
1785and 1715
(b)
892.5 and 857.5
(c)
89.25 and 85.75
(d)
178.5 and 171.5
Question ID - 50293 | SaraNextGen Top Answer
An amplitude modulated signal is given by V(t)=10[1+0.3cos(2.2×104)]sin(5.5×105t). Here t is in seconds. The sideband frequencies (in kHz) are, [Given
(a)
1785and 1715
(b)
892.5 and 857.5
(c)
89.25 and 85.75
(d)
178.5 and 171.5
|
An amplitude modulated signal is given by V(t)=10[1+0.3cos(2.2×104)]sin(5.5×105t). Here t is in seconds. The sideband frequencies (in kHz) are, [Given |
|||
|
(a) |
1785and 1715 |
(b) |
892.5 and 857.5 |
|
(c) |
89.25 and 85.75 |
(d) |
178.5 and 171.5 |
1 Answer
127 votes
Answer Key / Explanation : (c) -
V(t)=10+
cosAsinB]
=10+
[sin(A+B)−sin(A−B)]
=10+
[sin(57.2×104t) −sin(52.8×104t)]
=57.2×104=2πf1
F1=
=9.1×10−4
≈91 KHz
f2=
≈84 KHz
Side band frequency are
f1=fc −fw=
≈85.00 KHz
f2=fc+fw=
≈90.00 KHz
127 votes
Answer Link
127