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**1. The prIoblem statement, all variables and given/known data**

You are the chief of the Angry Birds (Google it, if you don’t know the reference...it’s not important). You can shoot red birds from a catapult, and they will fly as projectiles under the effect of gravity. Gravity points downwards and has magnitude g = 9.80 m/s2 . Your goal is to hit some nasty green pigs, who have stolen your Angry Bird Eggs. You are able to adjust the angle θ and speed v of the projectile, as it leaves the catapult. The projectile leaves the catapult at a height h above the ground.

a) First, consider the case when a single green pig is placed on the ground, at a distance d from the foot of the catapult. Find a relation between the angle and speed required to hit it. Remember to draw a sketch of the situation.

b) Next consider the case where there are two green pigs. One on the ground at a distance d as before, the other at a distance l < d, and placed on a pole of height h. What should you choose for θ and v in order to hit both pigs 1 with the same red bird? Why must one require l < d? Remember to draw a sketch of the situation.

## Homework Equations

On 1a) I came to the equation: Vi = sqrt((gd^2)/(2cos^(2)θ(h+d*tanθ)

## The Attempt at a Solution

I think i have to somehow use the equation from a in order to find the V initial and angle but I don't know how.

Because the distance between the two objects isn't given and the projectile can hit with either a small angle and large innitial speed or a large angle and low speed. The fact that I need to find an expression for both of these when the distance isn't given is what's troubbeling me and any hints or pointers to wich direction I should go next would be much appreaciated :) (sorry for my bad english, but I hope you understand)

This is the drawing that came with it btw

The task is given to the chapter about projectile motion and i think I'm supposed to use projectile motion to solve it.

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