Start with the quantity
Which variable actually answers your question?
From rulers and thermometers to data loggers, video analysis, CO₂ sensors and Python - with data types, mathematics, topic examples and limitations.
Measuring equipment does not automatically make an IA strong. The measured quantity must match the research question, the data must be reproducible, and you must explain resolution, accuracy, uncertainty and limitations. This guide connects common devices with mathematical methods and possible topic directions.
Which variable actually answers your question?
A display in 0.1 increments does not automatically prove ±0.1 accuracy.
Run a short pilot before collecting the full series.
Multiple trials reveal variation, outliers and uncertainty.
Keep original files, settings and timestamps traceable.
Heat, electricity, sport, personal or health data require additional safeguards.
Use these tools to measure length, diameter, thickness, angle and geometric distance. A calliper is valuable when millimetres or tenths of a millimetre matter; a protractor supports projectile, light, solar and slope experiments.
Record resolution and measurement method. Repeat readings and keep the same reference points.
A kitchen scale is sufficient for gram-level readings; a precision balance is better for evaporation, filter residue, electrodes or small material samples. Mass time series can be analysed with linear, exponential or piecewise models.
Use the same container, tare before each run, and protect the balance from draughts and splashes.
Measuring cylinders provide reproducible volumes; pipettes are useful for small, accurately dispensed quantities. They support concentration series, density measurements and controlled flow or mixing experiments.
Read the meniscus at eye level. Chemicals and hot liquids require appropriate school-lab supervision and protection.
Time measurement is central to motion, reaction, cooling, oscillation, flow and decay. A phone timer is enough for slow processes; video or a light gate is much better for short intervals.
Separate device resolution from human reaction delay. Manual timing requires many repetitions.
A contact probe measures the temperature of an object, liquid or the air at the sensor. Data loggers record at fixed intervals, making them ideal for cooling, conduction, insulation and daily cycles.
Check immersion depth, response time and calibration. A liquid probe should not touch the vessel wall.
An IR thermometer measures surface temperature at a point without contact. A thermal camera produces spatial temperature fields for profiles, area means, cooling curves and image analysis.
Emissivity, reflections and distance affect readings. Do not infer medical diagnoses from skin images; anonymise any personal imagery.
Hygrometers, moisture sensors, anemometers, rain gauges and pressure sensors create environmental time series suitable for multiple regression, seasonal patterns and controlled comparisons.
Do not expose sensors to sun or rain unless rated for it. Document a constant location and measurement height.
Lux meters measure illuminance; suitable solar sensors or multimeters can measure electrical output. They support inverse-distance models, angle of incidence, shading and daily cycles.
Lux is weighted to human vision and is not identical to radiant power. Control sensor orientation and ambient light.
A multimeter measures voltage, current and resistance. With a defined load it can support battery-discharge, internal-resistance, solar-cell and sensor-response investigations.
Use only safe low-voltage circuits. Connect current ranges correctly; mains electricity is not suitable for a student experiment.
These devices measure tension, compression, spring force and sometimes torque. Typical uses include Hooke’s law, friction, failure load, levers and optimisation of mechanical models.
Do not exceed rated loads. Fracture tests need eye protection, containment and competent supervision.
Microphones provide waveforms and spectra; sound-level meters report levels in decibels. Software supports Fourier analysis, resonance, attenuation and reverberation time.
Keep microphone position and gain fixed. Protect hearing and avoid unnecessary sound levels.
Video makes position, angle and time measurable frame by frame. Photographs support area fractions, symmetry, fractals, perspective and spatial interpolation. Include a calibration length in the image.
Fix the camera, control perspective and record the frame rate. Obtain consent before recording people.
Many phones record acceleration, angular velocity and magnetic field. This supports oscillation, rotation, travel, inclination and relative field measurements.
Document sensor axes and sampling rate, subtract background values and secure the phone safely.
GPS and trackers provide position, distance, speed, elevation, time and sometimes heart rate. They support real motion datasets, routes, elevation profiles and statistical comparisons.
GPS errors increase indoors and near tall buildings. Protect privacy and do not publish precise home or health data.
Heart-rate, reaction-time or simple breathing sensors can record temporal patterns and differences between conditions. They are for low-risk observation, not diagnosis or self-intervention.
Consent, anonymisation and school rules are essential. Do not conduct risky exertion, medication trials or diagnoses.
These sensors quantify properties of solutions, enabling calibration curves, concentration models, temperature corrections and time-dependent mixing or reaction studies.
Use only safe substances and school-appropriate concentrations. Rinse and calibrate probes and document temperature dependence.
A suitable NDIR CO₂ sensor records concentration, often with temperature and humidity, over time. It supports rise, decay and air-exchange models.
Do not deliberately enrich occupied rooms with CO₂ or seal people inside. Record warm-up time, drift and sensor position.
Light gates, ultrasonic sensors, force plates, spectrometers, magnetic stirrers or precise data loggers can support demanding questions. A device is useful only when its measurement matches the research question and its operation is understood.
Agree access with the teacher. Test limits, calibration, safety rules and data export before the main data collection.
Models provide controlled geometry, interchangeable parameters and repeatable trials. A 3D printer can produce channels, blades, vessels, bridges, tessellations or sensor mounts.
Document print settings and dimensional error. Physical models simplify reality; those assumptions belong in the reflection.
These tools store data, run regressions, create graphs, calculate residuals, simulate random processes and solve equations numerically. They do not replace an explanation of the mathematics.
Document formulas, data ranges, software version and settings. Explain central results rather than presenting black-box output.

d3ee170a-0cd4-40a0-a47d-3cf96c77c05d.jpegThe photographed device is not a sensor; it is a SATA docking station with a KingSpec SSD inserted. It is useful for securely storing, versioning and transferring large video, thermal-image, audio or sensor datasets. A traceable folder structure can be as important as the measuring device.
Verify the drive model and backups before initialising or formatting. Keep at least two copies and encrypt or anonymise personal data. The exact dock model is not legible in the photograph.
An expensive sensor does not replace a clear research question or transparent mathematics. A ruler or phone may be enough for a strong paper when experimental design, analysis and reflection are convincing.