A 0.50-kg block attached to an ideal spring with a spring constant of 80 N/m oscillates on a horizontal frictionless surface. When the spring is 4.0 cm longer than its equilibrium length, the speed of the block is 0.50 m/s. The greatest speed of the block is:

The greatest speed is 0.711 m/s

Explanation:

The total energy is only kinetic energy (no elongation in the spring), thus, the greatest speed of the block is equal:

Where

m = 0.5 kg

vi = 0.5 m/s

k = 80 N/m

s = 4 cm = 0.04 m

Replacing:

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