What is the period and frequency of the square wave shown in the video?

Conditions

• The function is periodic.
• The horizontal axis represents time in seconds.

Reasoning, step by step

1. Identify the time it takes for the waveform to complete one full cycle.
2. Write the period as $T = 2\pi$ sec/cycle.
3. Apply the reciprocal relation between period and frequency.
4. Calculate the frequency as $freq = \frac{1}{T} = \frac{1}{2\pi}$ cycles/sec.

Example

The board writes $T = 2\pi \frac{sec}{cycle}$ and $freq = \frac{1}{2\pi} \frac{cycles}{sec}$ next to the square-wave graph.

Common misconceptions

• Assuming the period is the total time shown on the axis rather than the time for one cycle.
• Confusing the units of period (seconds per cycle) with frequency (cycles per second).

Watch the explanation

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