An electrical discharge excites the He atom from its ground state (arbitrarily assigned the energy E1 = 0) to its excited state of 20.61 eV. The excited He atom collides with a Ne atom in its ground state and excites this atom to the state at 20.66eV. Neon atoms make a variety of downward transitions in falling from the E4* down eventually to level E1. This laser can produce a green or a red laser beam. From the data in the figure, (a) what is the wavelength of the red He–Ne laserlight? And (b) If the green light has a wavelength of 543 nm, what is the energy E2?

what best describes physical development during adolescence is the development of secondary sex characteristics happens at a rate unique to each individual.

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day

that would be because of both gravity and friction. so     c