TPR: Why Isn't This Projectile Motion

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MissionStanford

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An object is thrown with an initial speed of 7m/s directed 45 degrees above the horizontal from a cliff. After reaching the peak of its trajectory, it falls 20m to the ground below. What is the approximate ratio of the time it takes to hit the ground from the peak to the time is takes from its release to the peak of the trajectory?

I said 1 since I thought this is a projectile, so the time to reach the peak and reach the ground from the peak would be equal, but 1 is wrong. The right answer is 4.

Why? What's wrong with my reasoning? Why isn't this a projectile? What is a projectile? Isn't a projectile defined by the fact that its only influence is the force of gravity? Well, isn't that the case here?

Excuse my stupidity. I took a very basic physics class at high school and haven't taken Physics 1 or 2 at college yet (I am going to be this year, however - Studying ahead of time though, for the MCAT and because physics is very tough and poorly taught at my college).
 
It was thrown off a cliff, not over a flat surface.

It is still a projectile, but since it lands at a different height than the height from which it was launched, the time to reach its peak is less than the time to fall.
 
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