From: "JACK L. URETSKY (C)1998; HEP DIVISION, ARGONNE NATIONAL LAB ARGONNE, IL 60439" <JLU@HEP.ANL.GOV>
Date: Thu, 1 Jul 1999 14:13:26 -0500
Hi Rick-
But I thought the comparison is between two moving cars, each with
speed V, and a moving car with speed 2V and a parked car.
Regards,
Jack
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To simplify the discussion (somewhat) let's change the comparison to a
collision between two moving cars and one moving car and one parked car.
Now certainly a collision with the parked car at speed v is less serious
than a head-on with both cars travelling at v. In Michael's analysis below,
the assumption of equal times to come to rest is, I believe, the problem.
In the head-on, t will be smaller (assuming the center of mass will not move
once the cars make contact) than in the collision with the parked car (even
if that car doesn't move).
"I scored the next great triumph for science myself,
to wit, how the milk gets into the cow. Both of us
had marveled over that mystery a long time. We had
followed the cows around for years - that is, in the
daytime - but had never caught them drinking fluid of
that color."
Mark Twain, Extract from Eve's
Autobiography