Final figures vary widely. Depends on the speed at which the object hits us, depends on the angle at which it strikes (remember, these two together are what determine velocity in this sense).

Momentum= mv (mass time velocity)
Energy=(mv**2)/2 ((mass times velocity times velocity) divided by 2)

And actual destructiveness is utterly unpredictable, since it depends on not only momentum and energy, but where on the planet a potential impactor would strike: that so critically affects the mix of potential ejecta, and potential secondary effects.

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On the kinkometer, my kink measures as a sine wave.