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A spring with spring constant k = 200 N/m is suspended vertically with its upper end fixed to the ceiling and its lower end at position y = 0. A block of weight 20 N is attached to the lower end, held still for a moment, and then released. What are (a) the kinetic energy K, (b) the change (from the initial value) in the gravitational potential energy ΔUg,and (c) the change in the elastic potential energy ΔUeof the spring-block system when the block is at y = −5.0 cm? What are (d) K, (e) ΔUg,and (f) ΔUe when y = −10 cm, (g) K, (h) ΔUg,and (i) ΔUewhen y = −15 cm, and (j) K, (k) ΔUg,and (l) ΔUewhen y = −20 cm?
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