A Professor Holds an Eraser Against a Vertical Chalkboard by Pushing

question 42

Multiple Choice

A professor holds an eraser against a vertical chalkboard by pushing horizontally on it. He pushes with a force that is much greater than is required to hold the eraser. The force of friction exerted by the board on the eraser increases if he:

• A) pushes with slightly greater force
• B) pushes with slightly less force
• C) stops pushing
• D) pushes so his force is slightly downward but has the same magnitude
• E) pushes so his force is slightly upward but has the same magnitude

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Definitions:

Exports

Goods or services sent from one country to another for sale.

Imports

Merchandise or services that are brought from one nation into another for retail purposes.

Trade Surplus

A situation where the value of a country's exports exceeds the value of its imports, indicating a positive balance of trade.

Exports

Goods or services produced in one country and sold to buyers in another, contributing to the exporting country's GDP.