Final answer:
The process of becoming electrically charged when walking across a carpet is known as static electricity, which is caused by the rubbing of materials transferring electrons.
Step-by-step explanation:
When you shuffle your feet as you walk across a carpet in the winter, you may become electrically charged through the process of static electricity or triboelectric charging. This occurs due to the rubbing of your shoes against the carpet, which transfers electrons from the carpet to your shoes, making you negatively charged. The separation of charges leads to polarization within the objects involved. The electrons do not travel from your shoes directly to your hands; instead, they cause a redistribution of electrons throughout your body. This causes parts of your body, such as your hands, to accumulate these excess electrons. Consequently, when you touch a metal door knob, the excess electrons are transferred from your hand to the doorknob, oftentimes resulting in a noticeable spark.