Hello! I've been studying for physics and come across a problem that I've been working on from the textbook. I would just like some clarification as we have not fully covered this subject yet in the class sessions.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A vector, Avector, has a magnitude of 15 w/ an angle of 25deg with x-axis, vector B has a length of 25 and makes an angle of 70 deg with x-axis. Compute the magnitudes and directions of the vectors: Cvector = Avector + 4*Bvector and Cvector = Avector - Bvector

2. Relevant equations

Problem 1: Cx = Ax - Bx and Cy = Ay - By

Problem 2: Bx = KAx and By = KAy

3. The attempt at a solution

For the 1st problem:

Ax = 13.6

Bx= 8.6

Ay = 6.3

By = 23.5

Leads to Cx = 5, Cy = -17.2

Size of Cvector = 17.9 from Pythagorean theorem

Angle of cvector = arctan (Cy/Cx) = -73.8

For the 2nd problem:

Bx = KAx = 4(13.6)= 54.4

By = KAy = 4(6.3) = 25.2

Now question here, since I have the multiplied 4B components, do I just treat the rest of the problem as an addition equation? So:

Cx = Ax + Bx and Cy = Ay + By

Cx = 13.6 + 54.4 = 68

Cy = 6.3 + 25.2 = 31.5

thank you for any help :)

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# Homework Help: Subtracting/multiply vector clarification on worked problem

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