Questions
Question 1
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A spring oscillator has \(k=120\,\mathrm{N\,m^{-1}}\) and amplitude \(0.050\,\mathrm{m}\). Find its total energy.
Question 2
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Where is the speed of an undamped spring oscillator maximum: at equilibrium or at a turning point?
Question 3
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If the amplitude of an undamped spring oscillator is doubled, by what factor does its total energy change?
Question 4
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An oscillator has total energy \(0.80\,\mathrm{J}\) and spring constant \(100\,\mathrm{N\,m^{-1}}\). Find its amplitude.
Question 5
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At \(x=0\) in an undamped spring oscillator, what are the spring potential energy and kinetic energy in terms of total energy \(E\)?
Question 6
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A \(0.25\,\mathrm{kg}\) mass on a spring has \(k=64\,\mathrm{N\,m^{-1}}\) and amplitude \(0.15\,\mathrm{m}\). Find its maximum speed.
Question 7
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A spring oscillator has amplitude \(A\). What fraction of its total energy is potential energy at \(x=A/2\)?
Question 8
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A spring oscillator has total energy \(2.5\,\mathrm{J}\) and amplitude \(0.25\,\mathrm{m}\). Find the spring constant.
Question 9
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An oscillator has \(E=3.6\,\mathrm{J}\) and mass \(0.80\,\mathrm{kg}\). Find its maximum speed.
Question 10
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A spring oscillator has \(A=0.20\,\mathrm{m}\) and \(\omega=10\,\mathrm{rad\,s^{-1}}\). Find the speed magnitude at \(x=0.12\,\mathrm{m}\).
Question 11
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At \(x=A/3\), what fraction of an undamped spring oscillator's total energy is kinetic energy?
Question 12
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A \(0.50\,\mathrm{kg}\) mass on a spring has speed \(1.2\,\mathrm{m\,s^{-1}}\) as it passes \(x=0.030\,\mathrm{m}\). The spring constant is \(200\,\mathrm{N\,m^{-1}}\). Find the amplitude.
Question 13
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At what displacement magnitude is the kinetic energy equal to the spring potential energy in an undamped oscillator of amplitude \(A\)?
Question 14
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An oscillator has maximum speed \(0.90\,\mathrm{m\,s^{-1}}\) and angular frequency \(6.0\,\mathrm{rad\,s^{-1}}\). Find its amplitude.
Question 15
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At what displacement magnitude is the speed \(80\%\) of its maximum value in an undamped oscillator of amplitude \(A\)?
Question 16
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An oscillator has amplitude \(A\). Derive the displacement magnitude where the speed is half its maximum speed.
Question 17
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A damp-free oscillator loses \(36\%\) of its mechanical energy in a brief interaction and then continues oscillating with the same spring constant. By what factor does its amplitude change?
Question 18
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A mass \(m\) on a spring \(k\) is released from rest at \(x=A\). When it reaches \(x=A/3\), a rough patch removes energy \(Q\) instantly without changing position. Derive the condition on \(Q\) for the mass still to pass through equilibrium, and find its speed there if it does.
Question 19
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A mass \(m\) on a spring \(k\) passes \(x=x_0\) with speed \(v_0\). Derive the amplitude using energy, and state the condition on \(x_0\) and \(v_0\) for the state to be physically possible.
Question 20
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A spring oscillator has amplitude \(A\). A sensor may be active only where the kinetic energy is at least a fraction \(q\) of the total energy. Derive the allowed interval of \(x\), and state the allowed range of \(q\).