The Forces of Gravity and Electromagnetism Are Long-Range Forces, Extending

question 9

Multiple Choice

The forces of gravity and electromagnetism are long-range forces, extending in principle from their source (mass and electric charge, respectively) to infinity. Why is it that, in the universe, only gravity extends to infinity, whereas electromagnetic forces are much more limited in extent?

• A) Gravity and electromagnetism are one and the same force, with electromagnetic effects extending over limited spatial ranges and transforming into gravitational forces at large distances from matter.
• B) Electromagnetic forces from charged particles will move other charged particles around to produce a uniform charge distribution and therefore zero electromagnetic forces, whereas gravity concentrates mass and enhances the overall gravity force.
• C) Electromagnetic forces from positive charges are canceled by negative charges, whereas there are no negative "masses" to cancel the gravitational force.
• D) All atoms are electrically neutral, so in reality the electromagnetic force never reaches beyond the size of an atomic nucleus.

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Definitions:

Demand

Demand refers to the quantity of a product or service that consumers are willing and able to purchase at various prices during a given time period.

Inverse Demand Curve

A representation of the demand for a good showing the maximum price consumers are willing to pay for a given quantity.

Perfect Price Discrimination

Perfect price discrimination occurs when a seller charges each buyer their maximum willingness to pay, extracting all consumer surplus.

Total Profits

The sum of earnings from a business operation, after all expenses have been deducted from total revenue.