4. at ti = 0 a ball is thrown straight upward from yi = 0 at an initial speed vi. while in the air it is in free fall. (a) sketch ay-t, vy-t and y-t graphs for the motion (b) what are the magnitude and direction of the acceleration while the boulder is  moving upward?  moving downward?  at the highest point? (c) when is the velocity of the ball zero? (d) find the maximum height ymax reached by the ball. (e) find the time at which the ball reaches this maximum height. (f) at what time is the ball moving at vi/2 upward? (g) at what time is it moving at vi/2 downward? (h) at what time does the ball return to its initial position? (i) how long is the ball in the air above some arbitrary height h? (j) check that your answer for (i) makes sense. if you set the height to h = 0, you should get the same answer as for part (h). if you set the height to h = ymax you should get δt = 0.

What elements are found in the inner and out core of the earth? the correct layers of earth's interior from the top to the center? what is the unwanted material that is removed from a mine called? how much stronger is an earthquake that registers 5 on the richter as opposed to 2? what occurs at a convergence plate boundary? the majority of the the earth's rock what is the most common element found in the earth's crust? what element is found in pyrite that contributes to acid mine drainage? why must mining companies post bond prior to permitting? how are bacteria being used in treating effluent from mines? what is a problem of acid mine drainage in rivers and soils? what do tectonic plates move on? why is gold smelting so damaging? how are artesian wells formed? where is dammed water colder than the river it flows into? what is one of the problems of uncontained aqueducts? what is the largest use of industrial water? underground sand and gravel formations that can store water? what type of water test measure acidity? which type of water test for cloudiness from suspended solids? what water test measures the amount of calcium and magnesium? these are all problems of coal power plants all of the following are advantages of riparian lands along rivers what type of water would be the warmest and have the least amount of dissolved oxygen? the zone of aeration is

Aplayground merry-go-round has a radius of 4.6 m and a moment of inertia of 200 kg-m2 and turns with negligible friction about a vertical axle through its center. a child applies a 26.0 n force tangentially to the edge of the merry-go-round for 15.0 seconds. if the merry-go-round is initially at rest, how much work did the child do on the merry-go-round?

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