A 400-Kg Box Sits Atop a 10

question 40

Multiple Choice

A 4.00-kg box sits atop a 10.0-kg box on a horizontal table. The coefficient of kinetic friction between the two boxes and between the lower box and the table is 0.600, while the coefficient of static friction between these same surfaces is 0.800. A horizontal pull to the right is exerted on the lower box, as shown in the figure, and the boxes move together. What is the friction force on the UPPER box?

• A) 19.3 N to the right
• B) 19.3 N to the left
• C) 23.5 N to the right
• D) 31.4 N to the right
• E) 31.4 N to the left

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Definitions:

American Designs

Architectural, fashion, or other design styles that originated in or are characteristic of the United States, reflecting its culture and history.

Slave Revolt

An armed uprising by slaves against their masters and the institution of slavery, often seeking freedom, such as the famous 1831 rebellion led by Nat Turner in Virginia.

Virginia

A state in the southeastern U.S., known for its significant history as the site of the first permanent English settlement in America at Jamestown and later as a key battleground in the Civil War.