Two voltages v1 = 200 sin(314t + 20°) and v2 = 200 sin (314t) are applied to vertical and horizonal plates of a CRO. Lissajous pattern obtained will be a/an _________.

Concept

When two sinusoidal signals of the same frequency and magnitude are applied to both pairs of deflecting plates of CRO, the Lissajous pattern changes with the change of phase difference between signals applied to the CRO

• When 0 < ϕ < 90o or 270o < ϕ < 360°: The Lissajous pattern is the shape of an Ellipse having a major axis passing through the origin from the first quadrant to the third quadrant.
   
• When 90° < ø < 180° or 180° < ø < 270°: The Lissajous Pattern is the shape of an Ellipse having a major axis passing through the origin from the second quadrant to the fourth quadrant.

Explanation

Given, v1 = 200 sin(314t + 20°) and v2 = 200 sin (314t)

The phase difference between both the inputs = 20°

Since the phase difference lies between 0° to 90°, therefore the Lissajous pattern on the screen of a CRO is an ellipse.

Additional Information