Question
Bryan Allen pedaled a human-powered aircraft across the English Channel from the cliffs of Dover to Cap Gris-Nez on June 12, 1979. (a) He flew for 169 min at an average velocity of 3.53 m/s in a direction $45^\circ$ south of east. What was his total displacement? (b) Allen encountered a headwind averaging 2.00 m/s almost precisely in the opposite direction of his motion relative to the Earth. What was his average velocity relative to the air? (c) What was his total displacement relative to the air mass?
1. $35.8 \textrm{ km, } 45^\circ \textrm{ S of E}$
2. $5.53 \textrm{ m/s}$
3. $56.1 \textrm{ km, } 45^\circ \textrm{ S of E}$
Solution Video