Question

Vector a with arrow has a magnitude of 12.2 units and points due west. vector b with arrow points due north. (a) what is the magnitude of b with arrow if a with arrow + b with arrow has a magnitude of 17.4 units? 21.2 incorrect: your answer is incorrect. units (b) what is the direction of a with arrow + b with arrow relative to due west? ° correct: your answer is correct. (c) what is the magnitude of b with arrow if a with arrow â b with arrow has a magnitude of 17.4 units? units (d) what is the direction of a with arrow â b with arrow relative to due west? ° correct: your answer is correct.

Answer 1

C = Sqrt (17.4^2 - 12.2^2) = 12.4
ArcTan (12.4/12.2) = 45.47 degrees above vector a,  which is 134.53 degrees measured on the xy-axis.