Question
MasenngPryscs Week 2: Kinematics . Gayle Chrome Secure https//session.masteringphysics.com/mycl/iterVicw offset-next&assignmentProblemD-82500249; Week 2 KinematicsItem 14 ltem 14 Part A Youre stanng out your window when youa soe a wawer talloon fall past in this problem, gnore a resstance It the baloon takes 0 23 s to cross the 1 0 m bgh window, from iwhat heght stove the top of the wndow was it dropped? Express your answer to two significant figures and include the appropriate units Hint 1. If you knew the velocity at the top of the window, seems like the problem would be more straightforward e are many unknowns in ths problem, but jast tocus on the time perod when the balloon goes past it seems ike there ate wo mportant quanttias thar velocity at the top of the wndow, and a the bo lom Can you find TWO DIFFERENT kinematics equatons involving those nso quanttes? so you should hawa two equarions in two urknowns, alowing you to solva for themt (And once you do heve the velocry at the top of the wndow the quesion hat is asked should be a more drect applicabon of basc knematcs My Answers Give up Incorrect; Try Again; 5 attempts remaining Continu M122017
Explanation / Answer
suppose it was dropped from h height above the top of window.
it was dropped so v0 = 0 { initial velocity}
Applying d= v0 t + a t^2 /2
h = g t^2 /2
t1 = sqrt(2 h / g)
and h + 1 = g t2^2 / 2
t2 = sqrt(2 (h + 1) / g)
t2 - t1 = 0.23
sqrt(2 (h + 1) / g) - sqrt(2 h / g) = 0.23
h = 0.53 m ........Ans