# Tag Info

### How can forces be added?

It is self-evident that successive displacements add by the tail-to-head arrow method. Velocities, being rates of change of displacement, add in the same way, as must momenta, and therefore forces, ...
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### How can forces be added?

Here is one way of looking at it that might help you. To add vector A to vector B in the diagrams you provided, take each vector and draw its horizontal and vertical component like in this image. It ...
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### Gravitational potential energy for more than two object

For an arbitrary number of particles, just sum that expression, $-Gm_im_j/|\vec r_i-\vec r_j|$, over all pairs $i$, $j$ of particles. This is easy to see if you imagine bringing each particle ...
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### How can forces be added?

Let's rearrange this last situation as you are regarding force instead of displacement. The above diagram actually more likely represent displacement. The forces seems to be on seperate points. This ...

### How can forces be added?

The idea of vectors addition, subtraction, resolution, etc. is found everywhere in life. Using basic trigonometry, one could show that some force $F$ that makes an angle $\theta$ with the horizontal ...
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Accepted

### A basic question on friction

Your mistake is assuming that the frictional force that acts on B, which is $f$, is equal to the force $F$ exerted on A. Since A exerts a force $f$ on B, then by Newton's 3rd Law, B exerts an equal ...
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