A plane flies 407 km east from city A to city B in 44.0 min and then 871 km south from city B to city C in 1.90 h. For the total trip, what are the (a) magnitude (in km) and (b) direction of the plane's displacement, the (c) magnitude (in km/h) and (d) direction of its average velocity, and (e) its average speed (in km/h)? Give your angles as positive or negative values of magnitude less than 180 degrees, measured from the +x direction (east).

Question

Henry · Answer

a. d = 407km[0o] + 871km[270o]

X = 407 + 871*cos270 = 407 km
Y = 871*sin270 = -871 km.

D = sqrt(407^2 + (-871^2)) = 961.4 km.

b. Tan A = Y/X = -871/407 = -2.14005
A = -64.95o = 64.95o S of E. = Direction.

c. V=D/T = 961.4/(1.9+0.7333)=2.63 km/h.

d. 64.95o S of E.