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That’s funny - I was just thinking that, after taking the 125a exam, phys 12a was significantly more difficult than 125a. The sets were (generally) longer, the midterms were both pretty easy, but the phys 12a final was a terrible mess for me, whereas the 125a final was a refreshing reprieve from the horrors of 106a. </p>
<p>In any case, WashDad I would guess that high-school physics preparedness doesn’t correlate as strongly to success in Caltech physics as one would generally think. So don’t stress about it too much just because your son hasn’t taken several years of college physics before showing up!</p>