# Tidal force Calculator

## Calculate the gravitational and tidal forces of the moon and the sun, and their respective ratios of those at apogee to those at perigee.

 Moon's mass kg distance km, eccentricity Sun's mass kg distance km, eccentricity Earth's mass kg, radius km
 Gravity is inversely proportional to the square of the distance, and tidal power is the cube of the distance.The tidal force of the moon is about 2.2 times larger than that of the sun.The ratio of the tidal force of the apogee and perigee is about 1.4 by the elliptical orbit of the moon.$\normal Gravitational\ force\hspace{30}F={\large\frac{GMm}{r^2}}\\[10]Tide\ force\hspace{30}T=-{\large\frac{dF}{dr}}R={\large\frac{2GMm}{r^3}}R\\[10]\hspace{110}R:\ radius\ of\ the\ Earth$

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