A mechanics question about work and vectors

AI Thread Summary
To find the angle between the applied force and the displacement vector, the dot product of the two vectors can be used. The formula for the dot product relates the angle to the magnitudes of the vectors and the cosine of the angle. Specifically, the equation is F · D = |F| |D| cos(θ), where F is the force vector and D is the displacement vector. By rearranging this equation, the angle θ can be calculated using the inverse cosine function after determining the dot product and the magnitudes of the vectors. Understanding this relationship is key to solving the problem effectively.
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this year i started studying physics, so this question might be easy but i couldn't do it... i'll be happy if you help me.

''A constant force (5N)i-7(N)j is applied on an object and it moves. The total displacement of the object is l=(3)i+(6)j+(3)k. Find the angle between the force and the displacement.''
 
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What specifically do you need help (or are having trouble) with? Please elaborate.
 
I don't know how to find the angle. How can I use the displacement information to find the angle?
 
How is the dot product of two vectors related to the angle between them?
 
Ah yes! Thank you very much. ^^
 

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