Actually there's a mistake in the math...
Your friend forgot to take into considerations Kovy's inital speed, which makes Roloson even later on the save.
(I'm finishing my PhD in Physics next week )
Well Mr. Physics genius... it never states that his shot increases the puck velocity by 15m/s. It only states that the puckvelocity after being shot is 15m/s. It is an ambiguous question, though.
If you want to get into the nitty gritty then you'd have to take into consideration friction from air as well (and hence Bell Centre humidity, since they're clearly in Montreal).
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