Here is an interesting question.(adsbygoogle = window.adsbygoogle || []).push({});

When we make measurements of weight on earth using a spring scale should we correct for the moon's gravity? The correction would be:

[tex]a_m = a_e\frac{M_m}{M_e}\frac{R_e^2}{d_m^2}[/tex]

where:

[itex]d_m[/itex] = 384,400 km (approximate distance of surface of earth to centre of moon)

[itex]R_e[/itex] = 6400 km (radius of earth)

[itex]M_m[/itex] = 5.98E24 kg (mass of moon)

[itex]M_m[/itex] = 7.35E22 kg. (mass of earth)

[itex]a_m[/itex] = acceleration due to moon gravity on surface of earth

[itex]a_e[/itex] = acceleration due to earth gravity on surface of earth

The correction (about g/293000 = 3.4 E-6g) would be subtracted when your location on the earth is facing away from the moon and added when your location is facing toward the moon. Or would it?

AM

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# Homework Help: Correcting for the Moon's gravity

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