A 1 kg block is placed between two horizontal springs of force constants 100 N/m and 300 N/m. Both springs are simultaneously compressed by 0.20 m and the block is released on a smooth surface. If its maximum kinetic energy is N joule, find N.
Physics · Work , Power and Energy · conservation of mechanical energy
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Question

A 1 kg block is placed between two horizontal springs of force constants 100 N/m and 300 N/m. Both springs are simultaneously compressed by 0.20 m and the block is released on a smooth surface. If its maximum kinetic energy is N joule, find N.

Physics · Work , Power and Energy · conservation of mechanical energy

G1 Physics · Accepted Answer

Initial spring energy = ½(k₁+k₂)x² = ½(400)(0.20)² = 8 J. At the position where both springs are relaxed, this becomes maximum kinetic energy, so N=8.