Oscilloscope trace analysis for DC supply switching

Steps:

• Vertical deflection on trace is 2 cm; with Y-gain of 1 V/cm, supply voltage V = 2 × 1 = 2 V.
• Horizontal distance for one on-off cycle is 1 cm; with time base of 0.02 s/cm, period T = 1 × 0.02 = 0.02 s.
• Frequency f = 1/T = 1/0.02 = 50 Hz (switched on 50 times per second).
• Compare to options: V = 2 V and f = 50 matches choice C.

Why C is correct:

• Matches calculated V from Y-gain formula (deflection × gain) and f from frequency formula (1/period), where period uses time base.

Why the others are wrong:

• A: Includes "V" unit but same values as C; likely formatting error, but C is precise match.
• B: Doubles both V (ignores actual 2 cm deflection) and f (ignores 0.02 s period).
• D: Same error as B, just repeated.

Final answer: C