QW Answer The Following On A NEW Sheet of Paper… 1. Define gravity. 2. T or F. A substance with a high specific heat takes a long time to heat up. 3. What is the difference between thermal energy and temperature? 4. What is a force? 5. T or F. Energy always flows naturally from cold to hot.

What is a force? A force is a push or a pull. If something is not moving, a push or pull could start it moving. If something is moving, a push or pull could stop it.

Four Fundamental Forces Of Nature Listed From Weakest To Strongest: 1. Gravitational Force 2. Weak Nuclear Force 3. Electromagnetic Force 4. Strong Nuclear Force

Gravitational Force What do you remember about gravity?

Gravitational Force Right now, you’re being pulled down by Gravity. With an acceleration of 9.8 m/s 2 We feel gravity almost all the time (not when we’re in outer space, but it’s still there), but it’s most obvious when stuff falls down.

History Of Gravity Galileo discovered that all objects fall at the same rate Scientists proved this on the moon with a feather and a hammer

Newton’s Laws of Gravity Extension of Galileo`s work All matter has gravity Gravity pulls The more mass, the more gravity The farther away, the less gravity

Gravitational force is a fundamental force that acts between any objects with mass Nobody knows why matter has gravity, but we do know exactly how it behaves. We think it behaves the same everywhere in the universe. Therefore, it is a Fundamental Force.

Weak Nuclear Force Weak nuclear force is stronger than gravitational force but acts over a very short distance range Responsible for decay of atoms causing radiation Beta decay is when a neutron splits into a proton and electron This creates radioactivity

Importance Of Weak Nuclear Force If the weak force were not to exist, many types of matter would become much more stable. Elements like plutonium and uranium could be handled without protection. Without the weak force, the sun would cease to exist. The weak force allows the fusion of protons and neutrons within the sun. The excess energy from this fusion is the sun`s source of heat!

Electromagnetism What familiar words make up ‘Electromagnetism?’

Electromagnetism is in anything that has a charge Your hair Electric currents Magnets The ink sticking to your notebook paper The paint sticking to the wall Car batteries Electrons/protons within atoms

History of Electromagnetism

Electromagnetism is a fundamental force that exists between anything that has a charge (positive vs negative) Electromagnetism is a stronger fundamental force than gravity but it also has long range effects We will be discussing electricity and magnetism in greater detail within the coming weeks…

Strong Nuclear Force This is the strongest of the fundamental forces The strong nuclear force is responsible for: 1. Holding the nucleus of atoms together against the repulsive force of protons 2.Helping to form subatomic particles such as protons and neutrons This force is strong but only acts over VERY small distances

CERN Super Collider Scientists use the CERN super collider to find new types of particles or building blocks of life Higgs Boson Particle watch?v=W4LZRLdyQl4 watch?v=W4LZRLdyQl4 he-universe/videos/the-large- hadron-collider he-universe/videos/the-large- hadron-collider

Grand Unified Theory (GUT) After Einstein discovered relativity and all that stuff, he spent the remaining 30 years of his life trying to figure out how these four forces fit together. Scientists are still trying to achieve this discovery.

Fundamental Forces in Physics Listed By Increasing Strength: Gravitational Force Attractive force between objects with mass Long range effects Weak Nuclear Force Cause neutrons to decade into a protons Short range effects times stronger than gravity Electromagnetic Force Attractive and repulsive Long range effects times stronger than gravity Strong Nuclear Force Hold the entire nucleus together Short range effects times stronger than gravity

Remember: GWES G ravitational, W eak Nuclear, E lectromagnetic, S trong Nuclear are the Four Fundamental Forces in order of increasing strength

4 Fundamental Forces Video Summary