Question

In a oscilloscope the input to the horizontal plates is a 100 Hz voltage signal. The lissajous pattern (A), (B) and (C) will be generated when different frequency voltage signals are applied to vertical plates. Match each lissajous pattern to the corresponding frequency by

P. $f_y=50Hz$
Q.$f_y=66.66Hz$
R.$f_y=150Hz$
S. $f_y=150Hz$
T.$f_y=200Hz$
U.$f_y=300Hz$

• A. A - P; B - S; C - T
• B. A - Q; B - S; C - T
• C. A - P; B - S; C - U
• D. A - P; B - S; C - U

Answer 1

The correct option is C A - P; B - S; C - U

(A)-(P):
$\frac{f_x}{f_y}=\frac{2}{1}$
$f_y=\frac{100}{2}=50Hz$

(B)-(S):
$\frac{f_x}{f_y}=\frac{2}{3}$
$f_y=100\times \frac{3}{2}=150Hz$
(C)-(U):
$\frac{f_x}{f_y}=\frac{1}{3}$
$f_y=3\times 100=300Hz$