An object with mass $0\mathrm{.}210$ kgkg is acted on by an elastic restoring force with force constant $10\mathrm{.}1$ N$/$mN$/$m$.$ The object is set into oscillation with an initial potential energy of $0\mathrm{.}150$ JJ and an initial kinetic energy of $6\mathrm{.}20102$ JJ$.$

Part A

What is the amplitude of oscillation?

Express your answer with the appropriate units.

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AA $=$

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SubmitRequest$$Answer

Part B

What is the potential energy when the displacement is one$-$half the amplitude?

Express your answer with the appropriate units.

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UU $=$

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Part C

At what displacement are the kinetic and potential energies equal?

Express your answer with the appropriate units.

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xx $=$

nothingnothing

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Part D

What is the value of the phase angle $$ if the initial velocity is positive and the initial displacement is negative?

Express your answer in radians.