Lesson 2.4 - Universal Law of Gravitation
VIDEO LESSON (25:07 min)
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UNIVERSAL GRAVITY
We know gravity as force that attracts objects towards the centre of the earth. Newton figured that it must be a more general force in between an objects. After studying the orbits of the Planets, he determine some proportionalities.

The larger the mass, the higher the force.



To make them equal we need a proportionality constant, G.
English physicist, Henry Cavendish, discovered the value 200 years after Newton.
\( G = 6.67 \times 10^{-11} Nm^2/kg^2 \)
UNIVERSAL GRAVITY FORMULA


Video is not accessible in some countries. If you cannot view it, you might need VPN to do so.
UNIVERSAL GRAVITY
We know gravity as force that attracts objects towards the centre of the earth. Newton figured that it must be a more general force in between an objects. After studying the orbits of the Planets, he determine some proportionalities.

The larger the mass, the higher the force.
ALSO...
The force must have an inverse square relationship
PUT IT ALL TOGETHER:
To make them equal we need a proportionality constant, G.
English physicist, Henry Cavendish, discovered the value 200 years after Newton.
\( G = 6.67 \times 10^{-11} Nm^2/kg^2 \)
UNIVERSAL GRAVITY FORMULA

BUT...

EXAMPLE PROBLEM #1
Determine the force of gravity between a \( 3.0 \times 10^3 kg \) car and a \( 1.0 \times 10^4 kg \) truck if they are \( 2.0 m \) apart.
EXAMPLE PROBLEM #2
Determine the force of gravity between the earth and the sun.
最后修改: 2026年03月1日 星期日 14:15