A spring has a constant of 875N/m. What hanging mass will cause this spring to stretch 4.5m?

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Complete the sentence to describe the law of conservation of energy. the law of conservation of energy states that energy cannot be created

You want to move a heavy box with mass 30.0 kg across a carpeted floor. you pull hard on one of the edges of the box at an angle 30∘ above the horizontal with a force of magnitude 240 n, causing the box to move horizontally. the force of friction between the moving box and the floor has magnitude 41.5 n . what is the box's acceleration just after it begins to move