AQA GCSE Combined science Physics Required Practicals

how do you conduct the specific heat capacity practical

• Heat a metal block using an immersion heater.

• Measure temperature change over time.

• Calculate SHC using energy, mass, and temperature.

what is the independent variable for the SHC practical

Time or energy input

what is the dependant variable for the SHC practical

temperature

what is the control variable for the SHC practical

Insulation, same metal type

what are the limitations of the SHC practical

Heat lost to surroundings

what are common errors made in the SHC practical

Not stirring / inaccurate thermometer

how do you conduct the resistance of a wire practical

• Use voltmeter and ammeter to measure voltage/current across wire of varying lengths.

• Calculate resistance for each.

what is the independent variable of the resistance of a wire practical

Length of wire

what is the dependant variable of the resistance of a wire practical

Resistance

what is the control variable of the resistance of a wire practical

Wire material, thickness

what are the limitations of the resistance of a wire practical

Wire heats up, changes resistance

what are common errors in the resistance of a wire practical

Inaccurate measurement of wire length

how do you conduct the I-V characteristics practical

• Change voltage across a resistor, filament bulb, and diode.

• Measure current for each.

• Plot I-V graphs

what is the independent variable of the I-V characteristics practical

Voltage

what is the dependant variable of the I-V characteristics practical

Current

what are the control variables of the I-V characteristics practical

Component type, ambient temperature

what are the limitations of the I-V characteristics practical

Bulbs heat up, affecting results

what are the common errors in the I-V characteristics practical

Polarity reversed for diode

how do you conduct the density practical

• Measure mass with a balance.

• Find volume (ruler for regular, displacement for irregular).

• Use density = mass ÷ volume.

what is the independent variable in the density practical

Object

what is the dependant variable in the density practical

Density

what are the control variables of the density practical

Water temp, equipment

what are the limitations of the density practical

Reading error from displacement

what are common errors in the density practical

Volume not measured accurately

how do you conduct the stretching a spring practical

• Add weights to spring, measure extension.

• Plot force vs extension.

what is the independent variable in the the stretching a spring practical

Force (weight)

what is the dependant variable in the stretching a spring practical

Extension

what is the control variable in the stretching a spring practical

Spring used, same intervals

what are the limitations of the stretching a spring practical

Spring may deform permanently

what are the common errors of the stretching a spring practical

Not measuring from correct zero point

how do you conduct the ripple tank practical

• Create standing waves (on string) or water ripples.

• Measure wavelength and frequency.

• Use wave speed = frequency × wavelength.

what is the independent variable in the ripple tank practical

Frequency

what is the dependant variable in the ripple tank practical

Wavelength or speed

what are the control variables of the ripple tank practical

Tension (string), water depth (tank)

what are the limitations of the ripple tank practical

Reflections cause interference

what are the errors in the ripple tank practical

Wavelengths not measured peak to peak