Hello! I'm new to the forums, have SOME physics under my belt as a civil engineering major. I have a hypothetical question to solve that has been driving me bonkers. At first, it sounded simple enough. Now, I must assume MANY things and don't know which set of equations to use to solve my problem! SO, an apple (of unknown hardness) of assumed mass=0.125 kg is thrown by a child at a window at a speed of approx.= 15 m/s from a distance of approx: 20 meters at a height of approx. = 1.5 m. The apple strikes the residential window (assume: tempered, not fully, glass) and embeds itself (i.e.: breaks the glass). What force was required to break this window? Or, in other words I guess, what is the maximum force the window can exert on the apple before it critically deforms? At first, I thought: PROJECTILE MOTION! But, that really just deals with pathways, not forces, rights? So, what about Newtonian balance of forces, F=MA? Or, should I skip all of this and use KE=1/2mv^2, PE=mgh and W=FD? But, how?? ARGH!! Help a gal out, would ya? THANKS!!