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Projectile Motion (1 Viewer)

Aerath

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Hey, sorta stuck on this question, any help is appreciated:

A stone is thrown so that it will hit a bird at the top of a pole. However, at the instant the stone is thrown, the bird flies away in a horizontal straight line at a speed of 10m/s. The stone reaches a height double that of the pole, and in its descent, touches the bird. Find the horizontal component of the velocity of the stone.
 

lolokay

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say the projectory of the stone is represented by y=-Cx2, so that the origin is the maximum point/height
if d is the distance the stone travels to get from a height of 2p (max) to p, then p = Cd2.
The distance that the stone travels in going from 2p to the ground would then be rt2 d (same distance to get from ground to 2p)
So the total horizontal distance travelled by the stone is d + rt2 d, whereas the total distance travelled by the bird is 2d

They cover each of these distance in the same time, so you can then show that vstone/dstone = vbird/dbird

vstone = 10(rt2 + 1)/2 m/s
= 12.07m/s
 

zaefr

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next question: calculate the velocity required to kick DiligentStudent in the balls if he has any.

dont forget the air "being a dick" resistance:D

shove love, theres a new troll in town
 

Aerath

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Horizontal component: 12m/s (2 sig fig.)

Lol, an easy question posted by a student who goes to a top 5 school. You're shit, GTFO forums please dumbshit.
Wow, I could've known that the answer was 12m/s just by looking at the back of the book. And given that you haven't done any working, you could've just taken the answer from lolokay. I would also like to thank you for promoting SBHS from 7th to Top 5. If only it was that easy. =P

Anyways, thanks lolokay.
 
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