# Physics - Projectile Motion

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"A person fires a bullet horizontally from a gun at the same instant that another bullet is dropped from the same height as the rifle barrel. Discuss which bullet will hit the ground first."

I'm thinking that the bullet that is dropped will hit first, because it does not have an x-component, unlike the other bullet. Am I right?

"One day in the jungle, professor Glick was stalking a rare species of monkey. He spotted one up in a tree and decided to shoot it with a dart. If the monkey begins to fall at the same instant that the dart leaves the barrel of the rifle, explain why the professor should aim directly at the monkey."

This one I do not understand. Why should he aim directly at the monkey?

• Physics - Projectile Motion - ,

Both bullets hit the ground at the same time. The vertical equation of motion is the same, and the initial downward velocity component (which determines the time to fall) is zero in both cases.

In the second question, one should aim for the monkey ONLY if the monkey is intially at the same elevation as the hunter. But that is not the situation here. The monkey is "up in a tree". You are right; the hunter should aim lower than the monkey's initial location. The "teacher", if you have one, is wrong. Congratulations.

• Physics - Projectile Motion - ,

Ah, I see! Thank you!