How do you do B,C,D? (Physics/Velocity)

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1 Answer
Feb 12, 2018

See below

Explanation:

The speed of a particle is given by the slope of the #x# vs #t# curve - the steeper the curve, the more the position changes for the same change in time.

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b) At the intersection marked in red, B's #x-t# graph is steeper, so B is moving faster. At the other intersection, marked blue - A is moving faster.

c) Somewhere in between these two times the tangent to B's #x-t# curve is parallel to A's (the blue straight line in the figure above) - this is when they share a common velocity. That there is such a point is a consequence of what is called the means value theorem of calculus.

d) The slope of B's #x-t# curve is easily seen to decrease over time - option (ii) is the correct one.