Question

Why does Newton’s law of universal gravitation apply to all objects in the universe?

Answer 1

\[\color{green}{F = G\dfrac{m_1m_2}{d^2}}\] The gravitational force of attraction between any two bodies depends on the product of their masses and the inverse square of the distance separating them. The law applies universally to all things that have mass and are separated from one another by some distance, regardless of what they are or where they are located.

Answer 2

Thank you! May I ask another question? @ghuczek

Answer 3

hi

Answer 4

How does a free-body diagram tell you about the acceleration of an object? @ghuczek

Answer 5

A free body diagram is used to draw all of the forces acting on an object. Once those forces are drawn on the free body diagram, an analysis is performed to determine in there is a net or unbalanced force acting on the object. If there is an unbalanced force acting on the object, you can then use Newton's second law \[\color{green}{\vec{F} = m\vec{a}}\] to determine the magnitude and the direction of the acceleration.

Answer 6

How does Archimedes' principle explain how much fluid is displaced by an object? @ghuczek

Answer 7

A body submerged displaces an equal amount of fluid as the volume submerged. The weight of the volume of the fluid displaced is the upward buoyant force experienced on the object. Archimedes' principle does not explain how much fluid is displaced. (The volume of the fluid displaced is the same as the volume of the object displacing that fluid.) Archimedes' principle has more to do with how the upward buoyant force can be determined as a result of that displacement of the fluid in which the object is partially or totally emersed.

http://en.wikipedia.org/wiki/Archimedes%27_principle

Answer 8

for floating objects, a body will displace its own mass of the fluid in which it floats. so an oil tanker will have displaced the water that is below its water line, and that amount of water will have the same mass as the tanker itself. as the tanker loads or unloads, it will rise or sink further into the water. those lines on a boats hull are a proxy for how laden a boat is. naval architects design around this principle.

if a body floats, then it simply displaces its own volume of the fluid.

Answer 9

http://www.physicsclassroom.com/class/circles/Lesson-3/Newton-s-Law-of-Universal-Gravitation