Quantum Chromodynamics 101


Gravity, the force we are all most familiar with, is also one of the least understood.  What we do know is that objects with large masses will accelerate toward each other. Gravity is also responsible for creating the sun, moon, planets, stars, as well as other celestial bodies.  Without gravity, these bodies would be nothing but gas within the universe.


Gravity is also what gives us our weight on the Earth.  So consider this hypothetical situation.  Suppose that a very powerful spaceship has transported two humans of equal weight (180 lbs.) to Jupiter and Mercury.  If we know that gravity increases between objects with greater mass, we should be able to predict on which planet we will weigh more.

Scroll over each image below to find the answers!



Click on the links below to move to the other forces.

Weak Force Electromagnetic Force Strong Force