A Boy Pulls a Wooden Box Along a Rough Horizontal

question 21

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

---

Definitions:

Morphine

A potent opiate analgesic drug used to relieve severe pain, derived from the opium poppy.

Pain Killer

Medication or drugs used to relieve pain, also known as analgesics.

Opiate

A type of narcotic derived from opium used for its pain-relieving properties; often refers to drugs that act on the opioid receptors.

Psychoactive Drug

A chemical substance that changes brain function and results in alterations in perception, mood, consciousness, cognition, or behavior.