Gravity


 * [|Vacuum Chamber Video] **

[|.Gravity and Inertia] Study Jams

According to the law of universal gravitation, all of the objects around you, including Earth and even this book, are pulling on you, just as you are pulling on them. Why don’t you notice a pull between you and the book? Because the strength of gravity depends in part on the masses of each of the objects. ** Mass ** **//is the amount if matter in an object//**. Because Earth is so massive, it exerts a much greater force on you than this book does. Similarly, Earth exerts a gravitational force on the moon, large enough to keep the moon in orbit. The moon also exerts a gravitational force on Earth. **//The force of gravity on an object//** is known as it ** weight **. Unlike mass, which doesn’t change, an object’s weight can change depending on its location. For example, on the moon you would weigh about one sixth of your weight on Earth. This is because the moon is much less massive than Earth, so the pull of the moon’s gravity on you would be far less than that of Earth’s gravity.
 * Gravity, Mass, and Weight **





1 Tell how the arrows compare on each side above.

2 Tell how the Earth's force on the Moon compares to the Moon's force on the Earth.

end ..........................................................................................................................

The strength of the force of gravity between two objects depends on their masses and the distance between them.

To see the difference between mass and weight and its relative connection to gravity, watch the video.

[|International Space Station] .................................................................................. Key Concepts  Gravity extends over all space  Weightlessness is a result of free fall  Orbital motion is a form of free fall

Mass Free Fall Newtons 1st Law [|European Space Agency Free Fall]

https://gizmodo.com/every-satellite-got-into-space-thanks-to-newtons-law-of-1706907868

Gravity History https://www.youtube.com/watch?v=2RdXQ6KJIe8

Good Which Way is Down Mass Gravity VSauce

[|Why does the Moon orbit the Earth?]

[|Why Doesn't the Moon Fall to Earth]

[|Vomit Comet Physics Girl]

Microgravity International Space Station

[|Gravity and Satellite Motion] https://www.sciencelearn.org.nz/resources/268-gravity-and-satellite-motion

[|Gravity in Space] Veritasium [|Gravity in Space] Sci Show

Here's a cool game that Galileo Galilei himself experimented to test gravity. Try it yourself. [|Galileo drops the ball]

Videos [|Galileo Incline] Plane (ramp) [|Galileo Incline Plane] (ramp) [|Projectile Motion]

[|Gravity Model Curved Space Spandex]

[|Gravity NatGeo]

MICROGRAVITY - Calandrelli - Physics Girl- Veritasium https://www.youtube.com/watch?v=BnLQTUnXMg8 https://www.youtube.com/watch?v=7v-viGyoZAU https://www.youtube.com/watch?v=q1_AJWZajEk https://www.youtube.com/watch?v=xdJwG_9kF8s

[|Newton Orbit Thought Experiment]

Changing to a Lower Orbit https://www.wired.com/2010/11/changing-orbits-and-changing-speed/

[|Tides Caused by Gravity]

Hubble is Falling, Atmosphere is a player http://spacescicottrell.wikispaces.com/Gravity

[|Gravity Documentary]

[|Gravity Bozeman]

[|Gravity Crash Course Kids] [|Gravity n Orbits Crash Course Astronomy] [|Tides Crash Course Astronomy] [|Gravity Crash Course Physics]

What is gravity? https://www.youtube.com/watch?v=p_o4aY7xkXg

Here's another simulation activity. http://www.messenger-education.org/Interactives/ANIMATIONS/grav_assist/gravity_assist.html

https://www.yahoo.com/news/yes-artificial-gravity-could-happen-155312059.html

Gravity Waves http://www.nobelprize.org/nobel_prizes/physics/laureates/1993/press.html http://www.techinsider.io/gravitational-waves-ligo-1974-hulse-taylor-2016-2 http://www.businessinsider.com/scientists-announce-detection-of-gravitational-waves-2016-2

[|Is Gravity an Illusion?]

Gravity Human Body https://www.youtube.com/watch?v=7CuYx9mZCQA

Gravitational waves and the Big Bang http://finance.yahoo.com/news/why-rumor-discovery-something-einstein-192436908.html http://www.ted.com/talks/allan_adams_the_discovery_that_could_rewrite_physics?language=en http://www.ted.com/talks/brian_cox_on_cern_s_supercollider#t-489543

[|The Big G] What is the difference between big "G" and little "g"... And what is gravitational lensing?

Falling faster than G.

http://isites.harvard.edu/icb/icb.do?keyword=k16940&pageid=icb.page197826&pageContentId=icb.pagecontent388782&view=watch.do&viewParam_entry=29307&state=maximize#a_icb_pagecontent388782

http://www.science20.com/news_articles/falling_down_without_enough_gravity_its_hard_for_astronauts_to_tell_which_way_is_up-144115

Falling object http://www.sciencebob.com/experiments/the_lincoln_dive.php

http://sciencefair.math.iit.edu/projects/galileo/

http://www.daviddarling.info/encyclopedia/G/GalileoG.html

Gravity & Orbit Model Ball 2 foot string weight (washers) tube

[|Force of Gravity and Falling Veritasium]

Falling Washers Starting at one end of a string, washers are attached the following distances apart: 0 cm, 10 cm, 30 cm, 50 cm, 90 cm at the When the string is released, the washers will sound out at constant time intervals. 

Falling independent of lateral motion Spin a ruler to knock two washers off a table.

Using gravity to accelerate(sling shot) a space probe. []

[|http://www.daviddarling.info/encyclopedia/G/GalileoG.htm]

[]

http://news.yahoo.com/testing-einstein-spaceships-094500788--politics.html

http://discovermagazine.com/2013/julyaug/23-20-things-you-didnt-know-about-gravity

=Newton's Laws and Weight, Mass & Gravity =

Did you know that mass and weight are not the same? This lesson describes the difference between the two as well as the effect of gravity on weight. Examples are used to teach you how to calculate weight based on mass and acceleration of gravity. 

Newton's Laws: Weight, Mass and Gravity
Most of us have seen images of men walking on the moon. Now, even though the astronauts are wearing really heavy suits, they seem to bounce around the surface of the moon with very little effort. How is it that we can bounce around on the moon with ease while jumping here on Earth requires a lot of effort? The answer to this question lies within the difference between mass and weight.
 * Mass** is a measure of how much matter an object contains, while **weight** is a measure of the force of gravity on the object. An object has the same composition, and therefore mass, regardless of its location. For example, a person with a mass of 70 kg on Earth has a mass of 70 kg in space as well as on the moon. However, that same person's weight is not the same since gravity is different in these locations. The person will weigh less on the moon because the moon has less gravity. To better understand the concepts of weight and mass, we must first consider gravity and its effect on objects.

What Is Gravity?
So what is gravity? ** [|Gravity]  ** is the attractive pull between two objects that have mass. The strength of gravity is directly proportional to the amount of mass of each object. In other words, the larger the objects, the greater the gravitational attraction between them. For example, the gravitational pull you experience on Earth is much greater than it would be on the moon because the Earth's mass is greater. An object with twice as much mass will exert twice as much gravitational pull on other objects.

On the other hand, the strength of gravity is inversely related to the square of the [|distance]  between two objects. For example, if the distance between two objects doubles, meaning they're twice as far apart, the gravitational pull decreases by a factor of 4. This is because 2 squared is equal to 4. This means the effect of distance on gravitational attraction is greater than the effect of the masses of the objects.

Gravity As a Force
Gravity is a force. A **force** is simply a push or a pull experienced by objects that interact with each other. The interaction can be direct or at a distance, which is the case of gravity. **Newton's laws** tell us that if an unbalanced force acts on an object, it will change the object's state of motion. In other words, the object will accelerate. Since gravity is a force, gravity causes objects to accelerate.

Acceleration Due to Gravity
Let's look at an example of how gravity causes acceleration. If you drop a ball from a cliff, you will notice that the speed increases as it falls - it accelerates due to gravity. We have determined the **acceleration of gravity** is 9.8 m/sec^2 - that is, for free-falling objects on Earth. **Free falling** simply means no other forces, except gravity, are acting on the object. For example, any effect of wind resistance would be neglected. The [|velocity]  of a free-falling object increases by 9.8 meters per second every second. Let's look at the speed of the ball as it drops over time. This is going to help us understand how gravity causes acceleration. As you see on the screen, the ball will accelerate to a speed of 9.8 meters per second in the first second of travel. Over the next second, the speed of the ball will again increase by 9.8 meters per second, meaning it's traveling at 19.6 meters per second. The same thing will happen during the third second of time, so the ball will be traveling at 29.4 meters per second. With each second, the ball's speed increases by 9.8 meters per second. The acceleration of gravity is so important that it has its own symbol. It is often abbreviated with the letter //g//. **//g// = 9.8 m/sec^2** - that's the acceleration of gravity here on Earth for free-falling objects.

Gravity and Weight
Well, what about weight? Weight is a measure of the force of gravity acting on an object. According to Newton's laws of motion, force is directly proportional to both mass and acceleration, and the equation for force is **//F// = //m//* //a//**, where //m// = mass and //a// = acceleration. We can use this equation to solve for weight. All objects on Earth, whether they are falling, thrown, or even sitting still, experience the effect of gravity. Therefore, we can determine the weight of an object using the acceleration of gravity.

Calculation of Weight
Let's look at an example. How much does a 100-kg man weigh on Earth? <span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">Let's first recall the formula for force. <span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">//F// = //m// * //a// <span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">Now substitute weight for force and the acceleration of gravity (//g//) for acceleration. <span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">Weight = //m// * //g// <span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">Now plug in the values for //m// and //g// and solve for weight. <span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">Weight = 100 kg * 9.8 m/sec^2 <span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">Weight = 980 kg * m/sec^2

Effects of Hyper Gravity Studied https://www.nasa.gov/missions/science/hyper.html

<span style="background-color: #ffffff; color: #555555; font-family: open_sansregular,helvetica,arial,sans-serif; font-size: 14px;">[|New Theory of Gravity]

Why is the Earth Round