Reference no: EM132450276

Big Bang

Points for each question are indicated. Use your own words.

1. Gravity is the weakest of all fundamental forces. So why is that gravity  rather than the strong force keeps the planets in orbit around the sun? (hint: think  strength and range)

2. Why is it that protons/anti-protons and neutrons/anti-neutrons are no longer being created by colliding photons (aka pair production)?

3. This question will require a google search. The text mentions the other kind of hadrons called mesons as a more exotic form of  matter.

• What are these particles?
• Where would we detect them?
• What is their 1/2 life?

Note, there are several different kinds of mesons so can either report average properties for the 3 questions or you can report on one type of meson.

4. Why aren't there "free" quarks (quarks not confined within a neutron or proton)?

5. For each of the following particle interactions:

I. Calculate the baryon number, lepton number and charge for each particle as was done in the text.

II. Based on your results, state whether the interaction could or could not occur.

a) 3 Protons + 1 electron ! 2 Protons + 1 positron + 1 neutrino + 1 neutron

b) 2 electrons + 2 protons ! 2 neutrinos + 2 neutrons

c) 1 Neutron + 1positron ! 1 Proton

d) 1 Neutron + anti-Neutron ! 1 Proton + 1 Neutron + 1 electron + 1 anti-neutrino

e) 1 anti-Proton + 1 positron ! 1 anti-neutrino + 1 neutron + 1 proton