Highest energy cosmic rays
3 x 10 eV
Same as a baseball pitched at 60 mph
Produced in abundance in the sun
6 trillion pass through a human hand per second
Every particle has an antiparticle
Quarks & Leptons
A proton is made of two up quarks and one down quark.
A neutron is made of one up quark and two down quarks.
An up quark has charge +2/3 e. A down quark has charge -1/3 e.
Three laser beams have wavelengths λ = 400 nm, λ = 600 nm, and λ = 800 nm. The power of
1 2 3
each laser beam is 1 W.
Rank in order, from largest to smallest, the photon energies E E , a1, 2 in the3e three
E 1 E >2E 3
Rank in order, from