Why do ice skates glide smoothly?
Show answer & explanation
Answer: Pressure melts thin water layer
Blade sharpness cuts through — Wrong. Sharpness helps control, but gliding comes from pressure melting thin water layer under blade that acts as lubricant.
Pressure melts thin water layer ✓ — Correct! Blade's narrow edge concentrates skater's weight—creates high pressure. Increased pressure lowers ice's melting point slightly (pressure melting). Thin water layer forms under blade—acts as lubricant reducing friction. Skate glides on water film! Water refreezes behind blade. Works best near 0°C—too cold (-30°C+) and pressure doesn't melt ice effectively. Same principle: snowball packing (hand pressure melts/refreezes)!
Cold reduces friction naturally — Wrong. Cold doesn't reduce friction—ice is actually more friction at very cold temperatures. Pressure melting creates lubricating water layer.