Questions
Question 1
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A \(12\,\mathrm{kg}\) object is in a gravitational field of magnitude \(4.0\,\mathrm{N\,kg^{-1}}\). Find its weight magnitude.
Question 2
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An object has mass \(20\,\mathrm{kg}\). If the local gravitational field halves, what happens to its mass and weight?
Question 3
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A \(75\,\mathrm{kg}\) explorer has weight \(255\,\mathrm{N}\) on a moon. Find the moon's local gravitational field magnitude.
Question 4
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A \(25\,\mathrm{kg}\) payload is outside a spherical body of mass \(7.0\times10^{22}\,\mathrm{kg}\), at \(2.0\times10^6\,\mathrm{m}\) from its center. Find the payload's weight magnitude. Use \(G=6.67\times10^{-11}\,\mathrm{N\,m^2\,kg^{-2}}\).
Question 5
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An object has weight \(W_R\) at radius \(R\) from a spherical planet. Find its weight at radius \(2R\).
Question 6
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Two probes have masses \(m\) and \(3m\). They are at radii \(R\) and \(2R\) from the same spherical source. Find the ratio of their weight magnitudes \(W_{3m,2R}/W_{m,R}\).
Question 7
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At what height above the surface of a spherical planet of radius \(R\) is an object's weight half its surface weight?
Question 8
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A \(5.0\,\mathrm{kg}\) object is in a local gravitational field \(\vec g=(-2.0\hat{\imath}-7.0\hat{\jmath})\,\mathrm{N\,kg^{-1}}\). Find its weight vector and magnitude.
Question 9
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A \(50\,\mathrm{kg}\) lander has weight \(300\,\mathrm{N}\) at radius \(8.0\times10^6\,\mathrm{m}\) from a spherical planet's center. Infer the planet mass. Use \(G=6.67\times10^{-11}\,\mathrm{N\,m^2\,kg^{-2}}\).
Question 10
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A body of radius \(R\) has surface weight \(W_s\). Derive the height \(h\) above the surface at which the weight has fallen by a fraction \(p\), so \(W=(1-p)W_s\). State the allowed range of \(p\).