A 400-Kg Box Sits Atop a 10

question 1270

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:

Parasympathetic Nervous System

Part of the autonomic nervous system responsible for rest and digestion, counterbalancing the sympathetic nervous system.

Chronic Illnesses

Long-term health conditions that require ongoing medical attention or limit daily living activities.

Sympathetic Nervous System

Part of the autonomic nervous system that activates the body's fight or flight response during times of stress.

Fight-or-Flight

A physiological response to perceived danger or threat, triggering a choice between standing firm and fighting or fleeing to safety.