CENCO® AP Physics Lab 2.20: Determining Planck’s Constant

Measure the wavelength and threshold voltage of an LED and calculate Planck’s constant.

Introducing the new CENCO AP Physics lab series!

Ideal for AP Physics 1 and 2, AP Physics C, IB DP Physics, and advanced/honors physics courses, each of the 35 experiments is aligned with the revised College Board AP curriculum. These innovative labs go way beyond traditional exercises, turning real to world scenarios into true guided to inquiry investigations. Students are given a goal, but the investigation is driven by their ideas. As they draw conclusions, students report their results using the Claim to Evidence to Reasoning model. The teacher guides and student manuals are authored and reviewed by AP Physics teachers with decades of combined experience, so you can trust the setups to be successful in your classroom. All labs come complete with instructions and materials for one lab group of 2 to 4 students. For your convenience, labs are packaged to allow you to purchase only what is required for each experiment.

In this innovative, two-part, inquiry-based investigation, students first design an experiment using diffraction to measure the peak wavelengths emitted by several LEDs. Then, they measure the threshold voltage of each LED, allowing them to calculate Planck’s constant to a high degree of accuracy. As with all our AP Physics labs, students support their conclusions using the Claim-Evidence-Reasoning method.