Why Is My Calculation of the Scalar Product Incorrect?

AI Thread Summary
The calculation of the scalar product of two vectors was incorrectly approached by using an angle of -100 degrees. The correct angle between Vector A and Vector B needs to be determined accurately, which is not 100 degrees as initially assumed. A diagram is recommended to visualize the vectors' orientations and find the correct angle. Additionally, the expected answer of 13.00 is disputed, indicating a possible miscalculation. Properly identifying the angle and re-evaluating the calculations is essential for obtaining the correct scalar product.
elpermic
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Homework Statement


Find the scalar product of the 2 vectors.
Vector A is north of east at 70 degrees with a magnitude of 3.60m
Vector B is south of west at 30 degrees with a magnitude of 2.40m

Homework Equations


ABcosx

The Attempt at a Solution


I did dot product using the formula, 3.60x2.40xcos(-100) and got the wrong answer.. The answer is 13.00. What the hell did I do wrong? I did as the formula said I should do and failed. I don't get it??
 
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elpermic said:
Vector A is north of east at 70 degrees …
Vector B is south of west at 30 degrees …

I did dot product using the formula, 3.60x2.40xcos(-100) …

Hi elpermic! :smile:

It ain't 100. :wink:​
 
elpermic said:
I did dot product using the formula, 3.60x2.40xcos(-100) and got the wrong answer.. The answer is 13.00.
(1) The formula calls for the angle between the two vectors. That angle is not 100°. (Draw a diagram.)
(2) The answer cannot be 13.
 

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