In this interactive and animated object, learners examine the operation of a semiconductor diode when it is forward and reverse biased. A brief quiz completes the activity.

In this animated object, learners examine the operation of a zener diode in the forward and reverse bias conditions. A quiz completes the activity.

Learners view animations showing how to change the connections to cause a DC motor to reverse its rotation. A short quiz completes the activity.

Students read about light-emitting diodes, including LED voltage and current, and how to protect against reverse voltage.

Users study a chart containing numbers 1 to 99 and look for trivial palindromes as well as double and triple iteration palindromes. The reverse and add technique is demonstrated.

In this animated object, learners study the operation of a ladder circuit that controls the rotational direction of a DC motor.

In this interactive object, learners examine the PN sections of a diode and the diode's forward- and reverse-biased operations. A brief quiz completes the activity.