The 0.75-kg bob of a pendulum is fired from rest at position a. if the spring is compressed 50 mm and released, determine (a) its stiffness k so that the speed of the bob is zero when it reaches point b, (b) the stiffness k so that when the bob reaches point c the tension in the cord is zero

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Adiver named jacques observes a bubble of air rising from the bottom of a lake (where the absolute pressure is 3.50 atm) to the surface (where the pressure is 1.00 atm). the temperature at the bottom is 4.00 ∘c, and the temperature at the surface is 23.0 ∘c.what is the ratio of the volume of the bubble as it reaches the surface (vs) to its volume at the bottom (vb)? if jaques were to hold his breath the air in his lungs would be kept at a constant temperature. would it be safe for jacques to hold his breath while ascending from the bottom of the lake to the surface?

When you hold a rectangular object, how does the area of the side that is resting on your hand affect the pressure and the force that the object exerts?