IGCSE Physics Practical Skills 5: Mechanics, Timing and Density
Cambridge IGCSE Physics practical notes on length, time, speed, mass, volume, density, displacement, repeats, tables, graphs, and uncertainty.
Q: What does IGCSE Physics Practical Skills 5: Mechanics, Timing and Density cover?
A: It gives a complete Paper 5 and Paper 6 preparation route for the named skill, including apparatus, variables, data, safety, and evaluation.
Aim
Determine a mechanical quantity such as speed or density using direct measurements and a method that reduces timing or reading uncertainty.
Apparatus and setup
- metre rule, measuring cylinder, balance, and stopwatch
- motion track, trolley, pendulum, or irregular solid as supplied
- marker positions and suitable stands or supports
- paper towels and spill tray for displacement work
Draw the apparatus as a working scientific diagram: use straight lines, label the parts that affect the method, and show where measurements are taken. Do not add decorative detail.
Method
- Identify the calculated quantity and list the direct measurements required.
- Choose the widest safe distance, time interval, or sample size that the apparatus permits.
- Read scales at eye level and record raw readings before calculating differences.
- For periodic motion, time several cycles and divide by the cycle count.
- Repeat the complete measurement and average concordant results.
- Calculate with consistent units and report a sensible number of significant figures.
Variables
- Independent variable: distance, mass, shape, or trial condition when a relationship is investigated.
- Dependent variable: time, speed, volume, or density.
- Controls: release method, start position, apparatus alignment, timing rule, and environmental conditions.
A control variable is not just something kept the same. State how it is kept the same so another student could repeat the comparison.
Recording and processing results
Use separate columns for direct readings and calculated values. Include units only in headings. For displacement, show initial volume, final volume, and volume difference.
Use one table for raw readings and calculated values when the relationship is simple. Put each unit in the heading, not in every cell. Preserve the instrument precision in raw data and round calculated values only at the end.
Safety
Secure ramps and stands, keep moving masses away from bench edges, wipe spills promptly, and do not overload measuring equipment.
