Timeline for Work over time; humans versus automobiles
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
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| Sep 12, 2017 at 2:25 | history | edited | Zaid | CC BY-SA 3.0 |
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| Sep 10, 2017 at 21:19 | comment | added | Erik | Is it reasonable to argue that if I can move an object with even the slightest acceleration (e.g 0.00001 m/s) over time, it will reach the same top speed regardless of weight? Because regardless of weight, you can always lower the acceleration indefinitely to ensure the forces required are below the maximum output of the engine? max_eng_output > mass_to_move * acceleration. Assuming the engine output and mass are constant, we can vary the acceleration to have the inequality be correct | |
| Sep 10, 2017 at 20:18 | comment | added | Zaid | It may take longer to reach top speed, but it will reach the same top speed | |
| Sep 10, 2017 at 20:11 | comment | added | Erik | Very interesting. But to gain higher speed, you must accelerate. To accelerate, you need a force F = ma. Bigger mass -> bigger force. Doesn't that mean that mass affects top speed? | |
| Sep 10, 2017 at 19:35 | comment | added | Zaid | Sure, I'm assuming that the car's driving on a flat surface when I say that mass has no role to play (on an incline the story's very different). It's basically because at top speed acceleration is zero, so the motive force (sourced from the engine) is completely counteracted by the resistive forces acting on the vehicle. The only way mass would play a role here is if some of the resistive forces are proportional to the vehicle's mass. Such forces do exist in reality but their contribution is next to negligible, which is why I feel justified in saying that mass has no effect on top speed. | |
| Sep 10, 2017 at 19:19 | comment | added | Erik | Excellent answer! Could you please elaborate how mass doesn't effect top speed? Are we disregarding the mentioned limiting factors then? | |
| Sep 10, 2017 at 19:18 | vote | accept | Erik | ||
| Sep 14, 2017 at 17:56 | |||||
| Sep 10, 2017 at 18:55 | history | answered | Zaid | CC BY-SA 3.0 |