Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Moment of tangential forces, Mt (A), and moment of normal forces, Mn (B), as the function of slipperiness: group averages and standard errors (bars). Solid lines represent the thumb at high-friction contact (HFC); dotted lines represent the thumb at low-friction contact (LFC).
