Two sinusoidal signals p(ω1t) = A sin &omrga;1t and

Two sinusoidal signals p(ω₁t) = A sin &omrga;₁t and q(ω₂t) are applied to X and Y inputs of a dual channel CRO. The Lissajous figure displayed on the screen is shown below figure.

The signal q(ω₂t) will be represented as

1. q(ω₂t) = A sin ω₂t, ω₂ = 2ω₁
2. q(ω₂t) = A sin ω₂t, ω₂ = ω₁/2
3. q(ω₂t) = A cos ω₂t, ω₂ = 2ω₁
4. q(ω₂t) = A cos ω₂t, ω₂ = ω₁/2

	ω₂	=	ω_y
	ω₁		ω_x

=	Number of times tangent touches top or bottom
	Number of times tangent touches either side

⇒	ω₂	=	1
	ω₁		2

⇒ ω₂ =	ω₁
	1

and q(ω₂t) will lead p(ω₁t) by 90°
∴ q(ω₂t) = A sin (ω₂t + 90°)
⇒ q(ω₂t) = A cos (ω₂t)