The vector $\overrightarrow { \mathrm { A } }$ has components +5 and +7 along the x and y axes respectively.If the vector is now rotated 90 degrees counterclockwise relative to the original axes,the vector's components are now
A)-7;-5.
B)7;-5.
C)-7;5.
D)7;5.
E)7;0.

Question

Quizplus · Accepted Answer

If we rotate a vector counterclockwise by 90 degrees, its x-component becomes the negative of its original y-component and its y-component becomes the positive of its original x-component. Applying this to the given vector, we get:
x-component = -7
y-component = 5
So, the answer is (C) F1F1F1S1F1F1F107;5.

The Vector A→\overrightarrow { \mathrm { A } }A Has Components +5 and +7 Along the X and Y

The Vector $\overrightarrow { \mathrm { A } }$ Has Components +5 and +7 Along the X and Y