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The IIHS just released this video of the CX-30 undergoing a 40 mph driver-side small overlap crash test.

It received an overall evaluation of "good".

 

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2021 Mazda CX-30 2.5T Premium
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Scary that that is only 40 mph.
Better the car absorbing all that impact than your body. The difference modern crumple zones make to the livability of crashes is huge, even though the damage seems much more substantial.

From what I can see in the video, the CX-30 has a fantastic array of crumple zones. They're meant to slow the deceleration (time it takes to go from 18 m/s to 0) so that the forces are not as high. This is because as memed to death, force can be estimated as mass x acceleration; where acceleration can be (very roughly) estimated by dividing our change in velocity over the time taken.

I couldn't find any estimates for these times, but lets just assume for ease of math that the CX-30 goes from 40-0 in 1.0 second (likely still less). And because of the considerable amount the car is absorbing compared to older ones, we would have to assume that an older model took that 40-0 hit in much less time, lets say .25s.

a_cx_30 = 18m/s / 1s = 18 m/(s^2)
a_old = 18 m/s / .25s = 76 m/(s^2)

The weight of the car does play a factor, and remember that the crumpling also ensures that your car isn't sprung into a rollover or worse (modern cars do not have as elastic collisions because of crumpling).

Anyways, the force felt on your body could be many multitudes higher on your body without crumpling, as because F=ma, split second differences in impact absorption time make exponential differences on the forces felt by occupants and the vehicle.

For an 80 kg person, a 40-0 collision in my CX-30 example is going to feel 1440 newtons, which equates to a little over 2g's, which tells me my time numbers are way too lenient. My sample older car would be 4 times that at 8g's, plenty enough to injure an occupant.

I know you probably weren't hating on it, but I get tired of people wishing for older cars that didn't get damage from small collisions.
 

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2020 CX-30 GS FWD, Snowflake White
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I agree, here is a more visual comparison in that regard, to show the progress in safety.

 
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