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secondary 3 | E Maths
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1) i don’t know if this is a standalone qn but it doesn’t seem to link to the earlier qn
2) no answer is provided
For example, just before t = 6, the speed goes down to zero but at t = 6, the speed suddenly increases to 6 m/s without any time interval.
It’s like I am trying to jump off a building and suddenly in 0.001 seconds I find myself falling at terminal velocity.
Hence, the speed time graph would be invalid under this reasoning.
Had the portion after t = 8 come first before the t = 6 to t = 8 portion, the graph would have been a continuous one and would have made sense.
But then many distance time graphs are drawn this way, even though the instantaneous gain/loss in speed as represented by the two kinks on the graph is kind of impossible
Even if someone intentionally crashes a vehicle against a wall, the speed time profile would be one that allows a continuous decrease in speed (albeit for a extremely short time interval) rather than a sudden change in speed.
But I would give the answer along the same lines of impossible instantaneous decrease/increase if I were Unicorn
Edit : the graph could be correct if the object moving has the ability to carry out extremely quick acceleration (eg. Sports car)
https://www.math24.net/discontinuous-functions/
Examples of impossible time graphs :
https://slideplayer.com/slide/3873810/
http://www.shodor.org/interactivate/discussions/ImpossibleGraphs/
Or the derivative graph of the function graph is discontinuous.
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