Physics is the science that studies motion and matter and how both work with forces and energy.
It is a really big subject that has a lot of different “branches” of scientific study that include motion, sound, waves, electricity, light, sound, and even astronomy. This science covers the tiniest particles and atoms all the way to the largest objects in the universe.
We know gravity as the mysterious force that keeps everything from floating into space and instead makes everything fall towards Earth. One of the things that scientists have discovered is that all objects have gravity, but some objects, such as our Sun and the Earth, have a lot more gravity than other objects.
The amount of gravity doesn’t just depend on the “size” of an object, but instead, it depends on its “mass” as well as how close you are to the object.
The closer that you are to an object the stronger the gravity. The “mass” of an object is basically how tightly compact the molecules and atoms are as well as the number of molecules and atoms.
Without gravity, everything that we know would just fly away, so it’s incredibly important for our survival and the survival of all species on our planet.
The gravity of the sun is important because it keeps our Earth in a perfect rotation and all life on Earth requires the energy and warmth. Scientists refer to the distance between our Sun and Earth as the “Goldilocks Zone” We aren’t too far away or too close – we are “just right” for life to thrive on Earth.
Since they couldn’t see gravity, scientists in the past had to use mathematics to try to explain gravity. Sir Isaac Newton was the first scientist to figure gravity out and he created his “Newton’s law of universal gravitation.” Many years later, Albert Einstein improved on Newton’s theory in his own “theory of relativity.”
You might wonder why different things have different weight? On Earth, weight is the force of gravity on an object or how much force the gravity of our Earth has on the object and how hard it is pulling the object toward the surface.
If you stand on the roof of a 10-story building and drop two balls, one that weighs 5 lbs and one that weighs 1 lb at the same time, they will both fall towards the ground at the same speed and hit the ground at the same time. This is called the “equivalence principle.” Scientists have defined the letter “g” for standard gravity and it shows that all objects fall at this specific acceleration.
What does “1 g” stand for?
standard gravity on Earth
What is the reason that one object has stronger gravity than another object?
Who are the two scientists that made the greatest contribution to the topic of gravity?
Sir Isaac Newton and Albert Einstein
What effects does our moons gravity have on the Earth?
creates the ocean tides and ocean bulge
What is the nickname for the location of the Earth in our solar system that makes life possible?
What would happen if Earth didn’t have gravity?
everything would float into space