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Displacement is the straight line distance from points A to B. Distance is the travel length from points A to B ie A -> C -> D -> B


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In general, displacement is the distance from initial position to final position, where as distance is the length along the path that was taken. For example, if I run around a 400 m oval and return to my starting position, the distance I have traveled is 400 m, but the displacement is 0 since my initial and final positions are equal (therefore my average ...


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So taking your questions one at a time 1) The concave mirror will form a virtual image if the object is placed closer to the mirror than the focal point of the mirror. The formula for the position of the final image is $s'=\frac{sf}{s-f}$ where s is the object-mirror distance and f is the focal length of the mirror. You can see that if $s<f$ this will be ...


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The answer is: Solve Newton's second law. Really, $\vec F = m\vec a$ is meant to be a second-order differential equation, with the force dependent on position (and, sometimes, time). Writing it as $$ \vec F(\vec x,t) = m \frac{\mathrm{d}^2\vec x}{\mathrm{d}t^2}$$ makes manifest that the distance travelled by something, is, in general, the solution $\vec ...


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There is no edge of the universe. The standard model for cosmology is based on the FLRW metric. It is what happens when you assume the universe is homogeneous and apply general relativity. In this model the universe could have a finite volume that's not growing too fast, where paths just loop back on themselves. A photon in such a universe would keep ...


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Will an unhindered (un-scattered) photon go to the edge of the universe? To add to the answer of @RedAct : If you are thinking of the three dimensional part of the universe we observe now, it is an instantaneous universe, i.e. time t has one value. In this sense we are at the edge of the expanding universe, the right cutoff at 13.8 billion years in the ...


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The answer probably depends on how that question is interpreted. The universe is expanding. The ultimate fate of the universe isn't known for sure, but the growing consensus among cosmologists is that the universe will probably continue to expand forever. If that's the case, then a photon that leaves the Earth now will never catch up to what is currently ...



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