Physics
posted by Johana .
The location of a car at times t1 and t2 is given by the position vectors
r1= 15km due east + 20km due north (time t1) and
r2= 13km due west + 25km due north (time t2)
The units of distance are kilometers
a. What is the magnitude l^rl of the displacement?
b. What angle does the displacement ^r vector make with respect to the xaxis?
c. Draw a graph of the given situation.

a. r1 = (15 + i20)km.
r2 = (13 + i25)km.
r = r2  r1\,
r = (13 + i25)  (15 + i20),
r = 13 + i25  15  i20,
Combine liketerms:
r = 28 + i5,
r = sqrt((28)^2 + 5^2) =28.4km.
b. r = 28 + i5,
tanA = 5 / 28 = 0.17857,
A = 10.1 deg.,CW.
A = 10.1 + 180 = 169.9 deg.,CCW. Q2.