Three Blocks, Connecting Ropes, and a Light Frictionless Pulley Comprise

question 8

Multiple Choice

Three blocks, connecting ropes, and a light frictionless pulley comprise a system, as shown. An external force P is applied downward on block A. The system accelerates at the rate of 2.5 m/s². The tension in the rope connecting block B and block C equals 60 N.
-In the figure above,the external force P is closest to:

• A)170 N
• B)190 N
• C)210 N
• D)230 N
• E)250 N

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Definitions:

Negatively Charged

Refers to atoms or molecules that have gained one or more electrons, resulting in a net negative charge.

Molecule

The smallest physical unit of an element or compound, consisting of one or more atoms held together by chemical forces.

Ion

A molecule or atom that has acquired an overall electric charge from either losing or gaining electrons.

Hydrogen Bond

Hydrogen atoms bound covalently to either N or O atoms have a small positive charge that is weakly attracted to the small negative charge of other atoms, such as O or N; it can occur within a molecule or between different molecules.