- #1
james snail
- 3
- 0
Homework Statement
Exercise 1.3, chapter 3: if ex and ey lie along perpendicular lines, and ex has a magnitude of 4 and ey has a magnitude of 6, what are the components of the vector relative to the reference frame defined by the base vectors ex and ey?
Homework Equations
this relates to preceding exercise 1.2 in which vector of magnitude 144 makes 45 degrees with each of two perpendicular lines. I solved this with pythagorean theorem coming up with component vectors 6 x square root of 2, (4 sets with differrng signs.)also, per Hoffman, X + Y = V, and X= Vxtimesex, and Y = [V]ytimesey.
The Attempt at a Solution
since in 1.2 X and Y are each = 6 X square root of 2, I set Vxex = 6 X square root 2 thus 4ex = 6X square root 2. Answer ex = 3/2 square root of 2; similarly, ey = square root 2. This is incorrect as per Hoffmann, correct answers are + or - 18 X square root 2 and + or - 12 square root 2.will be most grateful to be shown how Hoffmann got his correct answers.