(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

1. Consider the point P at position ⃗rP = (−3.0 mm)ˆı + (4.0 mm)jˆ. Give an expression for rˆP , the unit vector in the direction of ⃗r.

2. Consider the point P from exercise 1 and another point Q at position ⃗rQ = (8.0 mm)jˆ. Give an expression for rˆPQ, the unit vector in the direction from P to Q.

2. Relevant equations

Not much really..maybe length formula

3. The attempt at a solution

I was wondering...x/sqrt(x^2+y^2) i +y/sqrt(x^2+y^2) plug it in to get (3/5)i+(4/5)j

For part two..would I subtract rQ-rP...so 4.0j-[-3.0i+4.0j)? Or would it be 4.0j-[(3/5)i+(4/5)j)? Then do the same..x/sqrt(x^2+y^2) i +y/sqrt(x^2+y^2)?

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# Homework Help: Vector Calculations

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