A Ladder 20 Feet Long Is Leaning Against the Wall

question 77

Multiple Choice

A ladder 20 feet long is leaning against the wall of a house (see figure) . The base of the ladder is pulled away from the wall at a rate of 4 feet per second. How fast is the top of the ladder moving down the wall when its base is 14 feet from the wall? Round your answer to two decimal places.

• A)6.86 ft/sec
• B)-6.00 ft/sec
• C)-3.92 ft/sec
• D)8.00 ft/sec
• E)-6.86 ft/sec

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Definitions:

Proprioceptors

Receptors in muscles, tendons, and joints that respond to changes in movement, tension, and position; enable an animal to perceive the position of its body.

Nociceptors

Pain receptors; free endings of certain sensory neurons whose stimulation is perceived as pain.

Chemoreceptors

Sensory cells or organs responsive to chemical stimuli, involved in detecting changes in the chemical composition of the environment or body.

Nociceptor

A sensory receptor that responds to potentially damaging stimuli by sending signals to the spinal cord and brain, which is interpreted as pain.