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They are currently testing that two cars impacting each other at 50mph each is similar to one hitting a solid wall at 100mph.

Regardless of this possible result, their small scale is bugging me.

The rig consists of a swinging arm, like a pendulum, and they are measuring the force exerted by the hammer coming down completely vertical and hitting a solid steel rod as an analogue for a solid wall. However, to compare what they say as “x” velocity and “2x” velocity they are starting the hammer at 45 degrees above the down/vertical to simulate “x” velocity and 90 degrees from the down/vertical to simulate the “2x” velocity.

Does anyone else realize that the change in height for the “x” velocity test will be sqrt(2)/2 and NOT 1/2 of the 90 degree, “2x” velocity, drop? Basic energy principle calculations will show that the 90 degree drop will not generate 2 times the velocity as the 45 degree drop. Thus, they should have used 90 degrees as “2x” velocity and 60 degrees as the “x” velocity.

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# Mythbusters Mistake

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