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3 years ago

6

A physics professor uses an air-track cart of mass m to compress a spring of constant k by an amount x from its equilibrium leng

th. The air-track has negligible friction. When she lets go, the spring launches the cart. What cart velocity should she expect after it is launched by the spring

1 answer:

zhenek [66]3 years ago

6 0

Answer:

v = √k/m x

Explanation:

We can solve this exercise using the energy conservation relationships

starting point. Fully compressed spring

Em₀ = $K_{e}$ = ½ k x²

final point. Cart after leaving the spring

$Em_{f}$ = K = ½ m v²

Em₀ = Em_{f}

½ k x² = ½ m v²

v = √k/m x

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