A Boy Pulls a Wooden Box Along a Rough Horizontal

question 36

Multiple Choice

A boy pulls a wooden box along a rough horizontal floor at constant speed by means of a force as shown. In the diagram f is the magnitude of the force of friction, N is the magnitude of the normal force, and F_g is the magnitude of the force of gravity. Which of the following must be true?

• A) P = f and N = F_g
• B) P = f and N > F_g
• C) P > f and N < F_g
• D) P > f and N = F_g
• E) none of these

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Definitions:

New Alleles

Variations in a gene that arise due to mutation, creating diversity within a population's gene pool.

Genetic Drift

Change in allele frequency due to chance alone.

Random Mating

A mating system where all individuals within a population have an equal chance of mating with each other, leading to genetic diversity.

Artificial Selection

The process by which humans breed plants or animals for particular genetic characteristics.