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A bullet is fired upward with a speed v0 from the edge of a cliff of height h (Fig. P3.22). (a) What is the speed of the bullet when it passes by the cliff on its way down? (b) What is the speed of the bullet just before it strikes the ground? (c) If the bullet is instead fired downward with the same initial speed v0, what is its speed just before it strikes the ground? Express your answers in terms of v0, h, and g. Ignore air drag. Assume the bullet is fired straight up in (a) and (b) and straight down in (c).
A ball is thrown upward with a speed of 35 m/s from the edge of a cliff of height h = 15 m (similar to Fig. P3.22). (a) What is the speed of the ball when it passes by the cliff on its way down to the ground? (b) What is the speed of the ball when it hits the ground? Ignore air drag. Assume the ball is thrown straight up.
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