Uploaded July 2021 | Updated September 2026, 2 hours ago
This video demonstrates an experiment to measure the value of g - the Earth's gravitational field strength at sea level.
This is achieved by dropping a small ballbearing from a variety of heights and timing how long it takes to fall. This is achieved using an electronic timer, a small electromagnet, a piezo electric pad and an interface box.
The equipment was produced by a friend of mine, but commercial versions of the apparatus are available from various educational suppliers.
To calculate g one must use the equation:
h = 1/2 g t^2
(where h is the height, g is the gravitational field strength and t is the time).
This can either be done by calculating g for individual results and taking an average, or by plotting a graph of 1/2 t^2 (y-axis) against h (x-axis) and adding a best fit line: The gradient of the line then gives the value of g.
This video demonstrates an experiment to measure the value of g - the Earth's gravitational field strength at sea level.
This is achieved by dropping a small ballbearing from a variety of heights and timing how long it takes to fall. This is achieved using an electronic timer, a small electromagnet, a piezo electric pad and an interface box.
The equipment was produced by a friend of mine, but commercial versions of the apparatus are available from various educational suppliers.
To calculate g one must use the equation:
h = 1/2 g t^2
(where h is the height, g is the gravitational field strength and t is the time).
This can either be done by calculating g for individual results and taking an average, or by plotting a graph of 1/2 t^2 (y-axis) against h (x-axis) and adding a best fit line: The gradient of the line then gives the value of g.










