BrainDen.com - Brain Teasers

# bonanova

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2. ## Paths of objects in free fall

It's one of the conic sections: circle, ellipse, parabola, hyperbola. Consider the angle arbitrary, like a pitcher throwing a baseball or a quarterback throwing a touchdown pass.
3. ## Paths of objects in free fall

If the effects of air resistance could be removed, what would be the shape of the trajectory of an object (say a football or a bullet fired into the air) in free fall under the influence of Earth's gravity?
4. ## Forgot one ?

If it's any consolation, for 5 seconds I thought that was the answer. But then I thought "that's not a puzzle." Then I had it.

Could it be
6. ## Forgot one ?

Well for starters it's NOT
7. ## check digit problem

Same approach. May not be sophisticated, likely not optimally efficient, but took only about 15 minutes. We're both "very close" and "exactly the same"? I guess we haven't proved the answers are unique. Starting with a different seed might yield different results. Anyway, here are my numbers:

9. ## check digit problem

Unless I'm counting wrong, it's
10. ## English

Are you saying they're not measurement units at all? Or just that they are not SI (rationalized MKS) units of measurement in particular?
11. ## Rights Of Passage

Here's some canon fodder, could it be
12. ## brain teaser sent by a friend that I can't solve

One way to find out is to send emails and see which addresses (don't) bounce.
13. ## Gold Bar on a Bus

True, it's reasonable. But could it be said that the bar was too large for the bus? @Mortie, did it say too large to "fit inside" the bus, specifically?

I think the fact that they might eventually meet and have to play each other would make that not possible.

Solution:
16. ## Really?

Is ii real?

@DejMar, that's not the result I get, but I also wonder

@JJLeDJ, nice approach. In those cases, an individual could receive both a silver and a bronze medal. But it doesn't quite fit the terms of the OP for the reason that it would be the team that won one of the medals, and it technically would not have been a single event. Welcome to the Den!

@jasen, I think you're on the right track, but look more closely at when the speeds are greatest.

@Brainy Binary, What you say is true. But note the OP asks about the average or expected shadow area.

I found an old clock in the basement and determined that its minute and hour hands have lengths in the precise ratio of 2:1, the minute hand being the longer. Having nothing else to do, I mounted a miniature radar speed recorder on the tip of the hour hand and arranged for it always to point to the tip of the minute hand. How much time will elapse after the greatest negative (receding) speed has been recorded until the greatest positive (approaching) speed is recorded?

DejMar has it. His answer (4) is the solution, and his answer (1) hinted at it. And 1948 is the last games this could have been possible.

All good ideas. What happened is a little more out of the box, tho. I suggest reading the OP carefully and don't constrain your answer unnecessarily. But by that I don't mean the wording is tricky. @CaptainEd, You're correct one one point: @Raphael lane, @Thalia, that's an interesting slant. To clarify,