Please don\'t give me another problem with different numbers! I have tried to wo
ID: 2191243 • Letter: P
Question
Please don't give me another problem with different numbers! I have tried to work this problem with other questions, and it has not worked. Thanks!!! When playing a game, a 49 kg boy jumps vertically upward from the top of a wardrobe with a speed of 5.5 m/s. (Ignore small changes in gravitational potential energy). Then he falls onto a mattress. (a) How fast is he going as he lands on the mattress, 3 m below? m/s (b) If the mattress behaves like a spring with spring constant 4.7 104 N/m, how far does he depress the mattress? mExplanation / Answer
Vo = 5.5 m/s Using Kinematic equation: Y = Yo + Vo y t + 1/2 gt^2 -3.0 = 0 + (5.5) t + (0.5)(-9.8)t^2 -3.0 = 0 + 5.5 t - 4.9t^2 Rewrite into standard quadratic form 4.9t^2 - 5.5t - 3.0 = 0 t = 1.52 seconds V= Vo + gt V = 5.5 + (-9.8)(1.52) V = -9.396 (negative sign indicates downward diection) B) Using conservation of energy At t= 0 Total energy = mgh + 1/2 mv^2 Total energy = (49)[(9.8)(3.0 + h) + (0.5)*(5.5)^2] = 1/2 kh^2 (49)((9.8)(3.0 + h) + (0.5)(5.5)^2) = (0.5)(4.7 x 10^4)h^2 480.2 h + 2181.725 = (2.35 x10^4)h^2 solve h...