An 80-Kg Man Is One Fourth of the Way Up $\degree$

question 58

Multiple Choice

An 80-kg man is one fourth of the way up a 10-m ladder that is resting against a smooth,frictionless wall.If the ladder has a mass of 20 kg and it makes an angle of 60 $\degree$ with the ground,find the force of friction of the ground on the foot of the ladder.

• A)7.8 x 10² N
• B)2.0 x 10² N
• C)50 N
• D)1.7 x 10² N

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Definitions:

Contractility

The ability of muscle cells and tissues to contract or shorten, generating force.

Tendons

Tough, fibrous tissues that connect muscles to bones, allowing for the transmission of force when muscles contract.

Canaliculi

Small, channel-like structures in bones that allow for communication and nutrient exchange between bone cells.

Haversian Canals

Channels extending through the matrix of bone; contain blood vessels and nerves.