To get to a concert on time, Dakota has to drive 122 miles in 2.00 hrs. (a) if he drove at an average speed of 55.0 mi/hr in a due west direction for the first 1.20 hr what must be his average speed if he is heading 30 degrees south of west for the remaining 48.0 min? (b)what is his average velocity for the entire trip?
d = r * t = 55mi/hr * 1.2hrs = 66 miles
driven.
122 - 66 = 56 miles remaining,
He has 48 min(0.8hrs) to drive the remaining 56 miles,
d = r * t,
56 = r * 0.8,
r = 56/0.8 = 70 mi/hr during the last
56 miles.
b. v = D/T = 122mi/2hrs = 61 mi/hrs