New Page 1

Answers to even problems, Quiz 3: Chapter 3

2. class notes; protractors and rulers aren't required on Test 1.

6.(a) r_x = 70.7 m; r_y = -70.7 (b) v_x = 282 m/s; v_y = 103 m/s (c) a_x = 0; a_y = -5.0 m/s² .

10.
(a) B = 5.7 and related angle = 45 degrees in Quadrant 2
(b) r = 2.2 cm and related angle = 26.6 degrees in Quadrant 3
(c) v = 100.5 m/s and related angle = 84.3 degrees in Quadrant 3
(d) a = 22.4 m/s²and related angle = 26.6 degrees in Quadrant 1

14. i and j are the two special unit vectors we use for component form.
(a) Vector -D = (8, 7) = 8i + 7j
(b) Vector -A lies in the first quadrant. Vector -B lies in the third quadrant. Vector -D lies in the first quadrant.
(c) Magnitude D = 10.6 and related angle = 41 degrees (in Quadrant 1.)

18. (a) vector -B = -4.3 i + 2.5 j (b) vector -B = -2.5 i + 4.3 j

20. Vector -A lies in the 4th quadrant at related angle 20 degrees. Vector -B lies on the y -axis, pointing North. Vector -C lies in the 3rd quadrant at related angle 70 degrees.