The H_α Spectral Line of Hydrogen Has a Wavelength of 656.3

question 8

Multiple Choice

The H_α spectral line of hydrogen has a wavelength of 656.3 nm as measured in the laboratory.The H_α spectral line is observed in light from a distant star at a redshifted wavelength of 789.0 nm.If Hubble's law is valid for this star,estimate how far is it from Earth if the Hubble constant is 22 km/s per million light-years.(c = 3.00 × 10⁸ m/s, 1 ly=9.461 x 1015 m , 1 y = 3.156 × 10⁷ s)

• A) 2.5 × 10⁹ ly
• B) 9.1 × 10⁸ ly
• C) 2.7 × 10⁸ ly
• D) 9.1 × 10⁷ ly
• E) 2.7 × 10⁷ ly

---

Definitions:

Spanish Missionary Period

The era from the late 15th to the 18th centuries when Spanish missionaries established missions to convert Native Americans to Christianity.

French and Indian War

A conflict between France and Britain from 1754 to 1763 in North America, part of the greater Seven Years' War, with Native American tribes playing key roles on both sides.

African Religions

Traditional religions practiced in various parts of Africa, often characterized by belief in a supreme being, ancestral worship, and spirituality connected to nature.

Middle Passage

The sea voyage that transported enslaved Africans across the Atlantic Ocean to the Americas as part of the triangular trade.