Year 12 AQA Practicals
These videos are a brief summary of each experiment. They include the theory, equipment, safety considerations and measurements to be taken.
You may find that with the equipment at your school there are some slight variations to the method and how you analyse your data. Please comment on the videos on my YouTube channel if you have any queries or would like to share your experiences with other students.
Stationary Waves on a String
A signal generator connected to a vibration generator can be used to set up a standing wave on a string. By changing the length of the string and varying the frequency until you reach the first harmonic you can investigate the speed of the wave along the string.
You can also vary the mass per unit length and the tension in the string as part of your investigation.
AQA Required Practical 1
Measuring the Wavelength of Light with a Double Slit
A laser will diffract and interfere when shone through a double slit. A series of dark and bright fringes can be measured on a screen which will then allow you to calculate the wavelength of light.
Be careful with the laser. Do not look at the beam or any reflected light from a shiny surface.
AQA Required Practical 2
Measuring the Wavelength using a Diffraction Grating
A laser will also diffract and interfere when shone through a diffraction grating. The distance to the first, second and third order maxima can be measured which will then allow the wavelength of the light to be calculated.

nustem  Diffraction
AQA Required Practical 2
Calculating 'g' using a FreeFall Method
Dropping a steel ball bearing through light gates can be used to find the acceleration due to gravity. Recording the time taken for it to fall as you then change the distance between the gates allows a graph to be plotted the the value of 'g' determined.

nustem  g via Freefall
AQA Required Practical 3
The Young's Modulus of Copper
This is a straightforward way to measure the Young's Modulus of a material. Copper wire is often used as it is stretched by weights hung over the edge of the bench, with the small extension carefully measured with a ruler.
Wear eye protection incase the wire snaps.
AQA Required Practical 4
The Young's Modulus of Steel (with a Vernier Scale)
This is a great way to measure the Young's Modulus if you have the equipment at your school. Steel wire does not extend much so the small extension is measured using a vernier scale.
Wear eye protection incase the wire snaps.
AQA Required Practical 4
Measuring the Resistivity of a Wire
Resistivity is a material property that can be measured by recording the resistance of various lengths of wire of a known cross section. Make sure that you only connect the circuit for a short time to minimise any heating effects of the current.
AQA Required Practical 5
Measuring Internal Resistance and E.M.F.
You can calculate the internal resistance of a cell by changing the external resistance of the circuit and recording the terminal p.d of the cell. When a graph is plotted the gradient is the negative value of 'r' while the yintercept should be equal to the e.m.f. of the cell.

nustem  EMF and Internal Resistance
AQA Required Practical 6