Determine Fundamental Constants with LEDs and a Multimeter
1 min read
Summary
While determining fundamental physical constants might seem like a task for large academic institutions with expensive labs, some can in fact be measured with inexpensive equipment.
For example, Marb’s Lab has managed to measure Planck’s constant, a key constant of physics that relates energy and frequency, using a simple kit consisting of five LEDs and a rotary switch, with help from a multimeter.
The experiment relies on Planck’s equation E=hf, with voltage measured across the LEDs standing in for energy E, and frequency measured with the help of LED datasheets.
Though the experimental setup can determine Planck’s constant to within 5%, more expensive apparatus can improve accuracy to within 1%, and measures it to eleven decimal places.
