When hair is wet it stretches to what percentage of its original length?

• A. 25%
• B. 75%
• C. 50%
• D. 100%

Answer: (C)

Wet hair stretches more than dry hair because water softens the keratin and temporarily breaks hydrogen bonds, acting as a plasticizer that lets the fiber elongate before it breaks. The typical maximum stretch before breaking is about 50% of its original length, so a hair that’s 10 cm long could extend to roughly 15 cm when fully stretched while wet. Pushing beyond that limit increases the risk of breakage. The other percentages don’t fit this common range: 25% is too little, 75% is usually beyond what wet hair can safely reach before snapping, and 100% would imply doubling the length, which isn’t attainable without breaking.