A ball initially at rest is dropped from an unknown height. Right before the ball hits the ground, it reaches a velocity of 30 m/s. Assuming air resistance is negligible, calculate the initial height of the object. A.
15 m
B.
30 m
C.
45 m
D.
75 m

Abeverage can is made of 3004-h19 aluminum alloy (elastic modulus 69 gpa, tensile yield strength 285 mpa, density 2.72 g/cm^3). the dimensions on the can are approximated as a thin-walled cylinder with a height of 4.83 inches, diameter of 2.60 inches. empty the can has a mass of 14.2 g. determine: a. the wall thickness of the cylinder b. assuming a pinned-pinned condition what is the critical load? c. assuming a fixed-fixed condition what is the critical load?