Multiple-Object Systems with Friction: a 4

question 38

Multiple Choice

Multiple-object systems with friction: 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:

Null Hypothesis

The null hypothesis is a statement in hypothesis testing that there is no effect or no difference, and it serves as a default position until evidence suggests otherwise.

Alternative Hypothesis

A hypothesis that proposes there is a statistically significant difference between two variables, contrasting with the null hypothesis.

Average Amount

The sum of numerical values divided by the count of values, providing a central or typical value for a dataset.

Significance Level

The likelihood of incorrectly dismissing the null hypothesis in a statistical analysis, commonly represented by alpha, when it is in fact correct.