Final answer:
Ripples are felt when sliding a finger on an AC-powered MacBook surface due to friction generating an electric charge and causing a ripple effect. The charge buildup and transfer between the finger and the surface create the sensation.
Step-by-step explanation:
When you slide your finger on an AC-powered MacBook surface, you may feel ripples due to electrostatic charge buildup. The friction between your finger and the surface generates an electric charge, causing the ripples. This happens because the MacBook's surface is made of materials that can hold and carry charges, like glass or plastic.
The ripples are a result of the charge being transferred between your finger and the surface. As you slide your finger, the charge builds up and creates a ripple effect. This effect can be felt when the charge is strong enough to cause a noticeable sensation.
It's important to note that the ripples are harmless and not a cause for concern. They are simply a result of the interaction between the charge on the surface and the charge on your finger.