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Physics question: How much force would it take to knock a smart car over if you hit it high on the side?
The force isn't quite the thing you're after, although you clearly have to exceed some minimum required to lift the car. Looking at the energy, it seem that ~5kJ would be enough to raise the car by tilting until the centre of gravity fell outside the ground contact area. 100kg cyclist at 13m/s has ~8.5kJ of kinetic energy. The problem would be in obtaining a coupling efficiency of 60%, i.e. making sure most of the kinetic energy was converted into gravitational potential energy in the car, rather than being wasted on stuff like work of fracture in your bones. I'd guess, based on a first approximation, that you couldn't tip it over just by crashing into it. On the other hand, you could probably tip it onto its tailgate by lifting the front :-)
gbj_tester-
Post of the year?
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Where are you placing the centre of mass? It must be pretty low down near the wheels.
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The problem would be in obtaining a coupling efficiency of 60%, i.e. making sure most of the kinetic energy was converted into gravitational potential energy in the car, rather than being wasted on stuff like work of fracture in your bones
I think it's reasonable to assume an inelastic collision, in which a crushed and broken combination of Khornight2 and bicycle temporarily sticks to the side of the car before falling away in a crumpled bloody heap. In which case, conservation of angular momentum (with the pivot point at the base of the car's tires on the far side) will give the initial angular velocity of the car's CoM, from which we can work out how much kinetic energy was delivered.
Do you still have the figures you found for the car's mass, width and CoM height ?
fizzy.bleach
Backstop
Nick.Earthloop
Physics question: How much force would it take to knock a smart car over if you hit it high on the side?
In a slightly unrelated question, how much force can a 17stone (100and something kg) cyclist exert at around 30mph?
(In case you can't read between the lines a smart car pulled out on me and I think I might have been going fast enough to knock it over... Which I would willingly break my shoulder to be part of)