Ted Radio Hour

We encounter friction every day—in all its forms—as we brush our teeth, go for a jog, argue with a friend. This hour, TED speakers explore how this force can be dialed up or down to improve our lives. Guests include tribologist Jennifer Vail, democracy activist Yaël Eisenstat, Sierra Leone's Minister of Education David Moinina Sengeh, and TV producer Elan Gale.