Timeline for Mass dropped on a spring
Current License: CC BY-SA 3.0
11 events
| when toggle format | what | by | license | comment | |
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| Jul 11, 2016 at 3:48 | comment | added | Shaz | Ok. So I will tell you guys a little of what we were trying to do. We are trying to make a force sensor: If you punch it, it should be able to tell you how much force was used in the punch. The idea is that the punch will compress the spring and if I know how much the spring is compressed I can tell the force of punch just by Hooks law. This particular problem occurred when I was trying to understand what happens when I drop a weight on the sensor from different heights. | |
| Jul 7, 2016 at 14:20 | comment | added | Floris | No you can't argue that it does not oscillate. If there is no damping, all potential gravitational energy must become elastic energy - and you get the result you calculated. But then the spring must oscillate indefinitely. If you allow for energy dissipation, the compression will be less. In the limit where you very gradually release the spring, it will come to rest at the equilibrium position - in that case gravity did some work on you, and less work on the spring. | |
| Jul 5, 2016 at 5:11 | comment | added | Shaz | Ok, first, as I said before, its not a homework problem. The calculation is part of a equipment we are building for our school. The mass does oscillate a little in practise. It comes up in the data of the experiment. But from a mathematical point of view that should not be important because that is a parameter of the design and you could argue for such a case, mathematically, that it does not oscillate. | |
| Jul 4, 2016 at 13:28 | review | Close votes | |||
| Jul 7, 2016 at 14:20 | |||||
| Jul 4, 2016 at 12:09 | answer | added | sammy gerbil | timeline score: 2 | |
| Jul 4, 2016 at 11:52 | comment | added | lemon | As a further hint to Peter's, if you compute the work done lowering the mass to equilibrium (so that it doesn't oscillate) then you will get your missing $1/2kx$ of energy. | |
| Jul 4, 2016 at 11:31 | comment | added | Peter Shor | We treat homework-like problems the same way as homework here, which means we try to give hints and not complete answers. | |
| Jul 4, 2016 at 11:30 | history | edited | Peter Shor |
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| Jul 4, 2016 at 11:28 | comment | added | Peter Shor | Hint: What happens when you let the object go, assuming no friction, is that it starts bouncing up and down on the spring and never stops. So if it stopped, some of the energy was dissipated by friction. | |
| Jul 4, 2016 at 11:22 | review | First posts | |||
| Jul 4, 2016 at 13:09 | |||||
| Jul 4, 2016 at 11:17 | history | asked | Shaz | CC BY-SA 3.0 |