Force of gravity and tides in conjunction

Storyboard

Gravity and centrifugal acceleration generate tides, the movement of oceans that raises and lowers their level with a frequency of 12 hours. Their origin can be generated by both the moon and the sun.

>Model

ID:(1523, 0)


Mechanisms

Description


ID:(15439, 0)


Variation of gravity perpendicular to the radius, in conjunction

Description

There is a contribution from the gravitational attraction of the celestial body that pulls water towards the equatorial region:



The hypotenuse of the triangle is related to the vertical leg by:

$R\sin\theta$



and the horizontal leg by:

$d - R\cos\theta$



Using the Pythagorean theorem, we have:

$R^2\sin^2\theta+(d-R\cos\theta)^2=d^2+R^2-2Rd\cos\theta$


ID:(11635, 0)


Variation of gravity parallel to the radius, in conjunction

Description

There is a contribution from the gravitational attraction of the celestial body that pulls water towards the radius, which tends to displace the water towards the equatorial zone:



The hypotenuse of the triangle is formed by the vertical leg:

$R\sin\theta$



and the horizontal leg:

$d - R\cos\theta$



According to the Pythagorean theorem, we have:

$R^2\sin^2\theta+(d-R\cos\theta)^2=d^2+R^2-2Rd\cos\theta$


ID:(11658, 0)


Model

Description



ID:(15434, 0)


Force of gravity and tides in conjunction

Description

Gravity and centrifugal acceleration generate tides, the movement of oceans that raises and lowers their level with a frequency of 12 hours. Their origin can be generated by both the moon and the sun.

Variables

Symbol
Text
Variable
Value
Units
Calculate
MKS Value
MKS Units
$a_c$
a_c
Acceleration generated by the celestial body, en conjunction
m/s^2
$d$
d
Celestial object planet distance
m
$\theta$
theta
Latitude of the place
rad
$M$
M
Masa del cuerpo que genera la marea
kg
$R$
R
Planet radio
m
$G$
G
Universal Gravitation Constant
m^3/kg s^2
$\Delta a_{cx}$
Da_cx
Variation of acceleration in the direction of the star, in conjunction
m/s^2
$\Delta a_{cy}$
Da_cy
Variation of acceleration perpendicular to the direction of the star
m/s^2

Calculations


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Equation
Solved
Translated

Calculations

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Equation
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Equations


Examples


(ID 15439)

There is a contribution from the gravitational attraction of the celestial body that pulls water towards the equatorial region:



The hypotenuse of the triangle is related to the vertical leg by:

$R\sin\theta$



and the horizontal leg by:

$d - R\cos\theta$



Using the Pythagorean theorem, we have:

$R^2\sin^2\theta+(d-R\cos\theta)^2=d^2+R^2-2Rd\cos\theta$


(ID 11635)

There is a contribution from the gravitational attraction of the celestial body that pulls water towards the radius, which tends to displace the water towards the equatorial zone:



The hypotenuse of the triangle is formed by the vertical leg:

$R\sin\theta$



and the horizontal leg:

$d - R\cos\theta$



According to the Pythagorean theorem, we have:

$R^2\sin^2\theta+(d-R\cos\theta)^2=d^2+R^2-2Rd\cos\theta$


(ID 11658)



(ID 15434)

To determine the variation of the acceleration perpendicular to the radius, we can use triangle similarity to equate the relation

$\displaystyle\frac{\Delta a_{cy}}{a_c}$



with the length

$d-R\cos\theta$



and the hypotenuse

$\sqrt{d^2+R^2-2dR\cos\theta}$

.

By triangle similarity, we have with that

$ \displaystyle\frac{ \Delta a_{cy} }{ a_c } =\displaystyle\frac{ R\sin\theta }{ \sqrt{ d ^2+ R ^2-2 d R \cos \theta } }$

.

(ID 11643)

Con la ley de la gravitaci n de Newton, con , es:

$ F = G \displaystyle\frac{ m_g M }{ r ^2}$



Se puede, con la definici n de la fuerza, con :

$ F = m_i a $



Y el radio al cuadrado:

$r^2=d^2+R^2-2dR\cos\theta$



Calcular la aceleraci n reemplazando el radio en la fuerza y despejando la aceleraci n. Esto da con la aceleraci n:

$ a_c = \displaystyle\frac{ G M }{ d ^2+ R ^2-2 d R \cos \theta }$


(ID 11644)

With acceleration generated by the celestial body, en conjunction $m/s^2$, celestial object planet distance $m$, latitude of the place $rad$, planet radio $m$ and variation of acceleration perpendicular to the direction of the star $m/s^2$, the relationship between the variation of acceleration and acceleration is:

$ \displaystyle\frac{ \Delta a_{cy} }{ a_c } =\displaystyle\frac{ R\sin\theta }{ \sqrt{ d ^2+ R ^2-2 d R \cos \theta } }$



And since the expression for acceleration is with acceleration generated by the celestial body, en conjunction $m/s^2$, celestial object planet distance $m$, latitude of the place $rad$, masa del cuerpo que genera la marea $kg$, planet radio $m$ and universal Gravitation Constant $m^3/kg s^2$:

$ a_c = \displaystyle\frac{ G M }{ d ^2+ R ^2-2 d R \cos \theta }$



It follows that:

$\Delta a_{cy} = GM\displaystyle\frac{R\sin\theta}{(d^2 + R^2 - 2dR\cos\theta)^{3/2}}\sim \displaystyle\frac{GM}{d^2}\displaystyle\frac{R\sin\theta}{d}$



Therefore, in the approximation d\gg R, we can approximate with by:

$ \Delta a_{cy} = \displaystyle\frac{ G M }{ d ^2 }\displaystyle\frac{ R \sin \theta }{ d }$


(ID 11645)

To determine the variation of the acceleration parallel to the radius, we can use triangle similarity to equate the relation

$\displaystyle\frac{\Delta a_{cx}}{a_c}$



with the length

$d+R\cos\theta$



and the hypotenuse

$\sqrt{d^2+R^2-2dR\cos\theta}$



By triangle similarity, we have with that

$ \displaystyle\frac{ \Delta a_{cx} }{ a_c } =\displaystyle\frac{ d - R\cos\theta }{ \sqrt{ d ^2+ R ^2-2 d R \cos \theta } }$


(ID 11647)

With acceleration generated by the celestial body, en conjunction $m/s^2$, celestial object planet distance $m$, latitude of the place $rad$, planet radio $m$ and variation of acceleration in the direction of the star, in conjunction $m/s^2$, the relationship is:

$ \displaystyle\frac{ \Delta a_{cx} }{ a_c } =\displaystyle\frac{ d - R\cos\theta }{ \sqrt{ d ^2+ R ^2-2 d R \cos \theta } }$



And as for acceleration generated by the celestial body, en conjunction $m/s^2$, celestial object planet distance $m$, latitude of the place $rad$, masa del cuerpo que genera la marea $kg$, planet radio $m$ and universal Gravitation Constant $m^3/kg s^2$,

$ a_c = \displaystyle\frac{ G M }{ d ^2+ R ^2-2 d R \cos \theta }$



Thus, we have:

$\Delta a_{cx} =GM\displaystyle\frac{d - R\cos\theta}{(d^2 + R^2 - 2dR\cos\theta)^{3/2}}\sim \displaystyle\frac{GM}{d^2}\left(1+\displaystyle\frac{2R\cos\theta}{d}\right)$



Therefore, in the approximation d\gg R, we can approximate with by:

$ \Delta a_{cx} = \displaystyle\frac{ G M }{ d ^2}\left(1+\displaystyle\frac{2 R \cos \theta }{ d }\right)$


(ID 11650)


ID:(1523, 0)