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Throwing an object while traveling with a speed

A paperboy is riding at 10 ft/s on a bicycle and tosses a paper over his left shoulder at 50 ft/s. **If the porch is 50 ft off the road, how far up the street should the paperboy release the paper to hit the porch?**

So i drew a diagram that looks like a right triangle (attached)

Attachment 18794

I found the hypotenuse of the triangle to be $\displaystyle \sqrt(2600) ft/s $

I figured if after he threw the paper at that speed then he would need to throw it $\displaystyle \sqrt(2600) ft $ before the porch.

It seems pretty far but i wasnt too sure about how else to go about this problem

Thank you for any help :D

Re: Throwing an object while traveling with a speed

Hi

I'm new member but i found the answer

on yahoo so here it is:

Call +y: direction of road, call +x: rightward direction

g: ground, b: bike, p: paper

Express relative motions as vectors. Neglect the vertical component of the paper's motion and assume it was the horizontal velocity that was given.

v_b:g = 10ft/s*<0,1>

v_p:b = 50 ft/s*<1,0>

Add them up to find velocity of paper:

v_p:g = v_b:g + v_p:b

v_p:g = <50, 10> ft/s

Express distance traveled of paper:

d = v_p:g * t

d = <50 * t, 10*t> ft/s

Set target:

d = <50 ft, x>

find x:

50ft = 50ft/s*t

t = 1sec

x = 10 ft

Conclusion: He should throw 10 ft uproad.