Sometimes, a crackling sound is heard while taking off a sweater during winters. Explain.

The crackling sound while removing a sweater in winter results from static electricity buildup:

1. Static Electricity Generation: In cold, dry conditions, materials like wool or synthetics create static electricity due to friction. When you wear a sweater, friction between it and your clothes or skin generates a static charge.

2. Electron Transfer: Rubbing between materials causes electron transfer, leading to an imbalance in electrical charges on the surfaces involved.

3. Electrostatic Discharge: Removing the sweater causes the accumulated static charge to discharge suddenly. This discharge produces a crackling sound and sometimes a small spark as electrons move to balance the charges.

4. Dry Air’s Impact: Winter’s dry air exacerbates static buildup since moisture in the air aids in charge dissipation. Dry conditions intensify static charge accumulation, leading to noticeable crackling.

To mitigate static buildup, use moisturizers to slightly increase humidity, avoid clothing prone to static, or use antistatic sprays or dryer sheets to reduce static cling in fabrics.