Lesson Plan

• Describe how the time‑base (horizontal) and y‑gain (vertical) controls relate to sweep speed and voltage per division.
• Calculate the frequency of a sinusoidal signal from the measured horizontal divisions and the time‑base setting.
• Determine the amplitude of a signal from the measured vertical divisions and the y‑gain setting.
• Apply CRO measurements to analyse a progressive wave on a string and identify resonance conditions.
• Use the CRO’s cursors or built‑in measurement functions to obtain accurate division counts.

• Cathode‑Ray Oscilloscope or digital oscilloscope
• Function generator
• Computer & projector for slides
• Worksheet with measurement tables
• Calculator
• Ruler or CRO division grid (optional)

Begin with a striking image of a wave displayed on a CRO to capture interest. Ask students to recall the sinusoidal wave equation and any previous experience using oscilloscopes. Explain that by the end of the lesson they will be able to extract quantitative frequency and amplitude values from the CRO screen.

1. Do‑now (5'): Quick quiz on wave symbols and basic oscilloscope terminology.
2. Mini‑lecture (10'): Explain time‑base and y‑gain, show the relevant formulas on the projector.
3. Guided demonstration (15'): Set the CRO to 0.5 ms/div and 2 V/div, measure horizontal and vertical divisions, calculate frequency and amplitude together.
4. Paired activity (15'): Students use a function generator and the CRO to record L_h and L_v for different settings, completing the worksheet.
5. Check for understanding (5'): Groups share one calculation; teacher confirms correct use of formulas.
6. Extension discussion (5'): Relate the measurements to a progressive wave on a string and discuss how resonance appears on the screen.
7. Summary & wrap‑up (5'): Review key steps and formulas.

Summarise how the time‑base and y‑gain enable quantitative analysis of wave signals. For the exit ticket, each student writes one frequency and one amplitude calculation from today’s activity. Homework: complete the worksheet with two additional CRO settings and reflect on how changing the time‑base affects the displayed waveform.