What Causes the Cosmological Redshift of Photons That Reach Earth

question 217

Multiple Choice

What causes the cosmological redshift of photons that reach Earth from distant galaxies?

• A) The photons have traveled through space that has been expanding and their wavelengths have expanded with it, becoming redder.
• B) The photons were emitted from the galaxies much earlier in time when the overall temperature of matter was much lower. Hence, the observed photons are redder the farther away from Earth they were produced.
• C) The photons were emitted by objects that were moving rapidly away from Earth and thereby have been reddened by the Doppler effect.
• D) The photons have moved from high-gravitational-field regions toward lower fields, thereby becoming reddened.

Differentiate between diastole and systole in terms of heart muscle movement.

Comprehend the circulatory path of blood through major veins and arteries.

Understand the historical development of knowledge regarding blood circulation.

Comprehend the structure, function, and lifespan of red blood cells, and the role of hemoglobin within them.

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Definitions:

Marginal Product

Marginal product is the additional output gained from increasing one unit of a variable input, holding all other inputs constant, in the production process.

Total Product

The total quantity of output that a firm produces with a given amount of fixed and variable inputs during a specified period.

Total Product

The total quantity of output that a firm produces, usually within a given time period.

Marginal Product

The additional output produced as a result of using one extra unit of a particular input.