A 40-Kg Mass, Initially at Rest on a Horizontal Frictionless Surface

question 87

Multiple Choice

A 4.0-kg mass, initially at rest on a horizontal frictionless surface, is struck by a 2.0-kg mass moving along the x axis with a speed of 8.0 m/s. After the collision, the 2.0-kg mass has a speed of 4.0 m/s at an angle of 37° from the positive x axis. What is the speed of the 4.0-kg mass after the collision?

• A) 2.0 m/s
• B) 2.7 m/s
• C) 4.9 m/s
• D) 2.4 m/s
• E) 3.6 m/s

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Definitions:

Repression

A defense mechanism in psychoanalytic theory in which unpleasant thoughts, memories, or feelings are pushed out of the conscious mind.

Repression

A defense mechanism in which unpleasant thoughts, feelings, or desires are excluded from conscious awareness.

Proactive Interference

The phenomenon where older memories hinder the recall of newly acquired information.

Automatic Processing

The unconscious encoding of incidental information and well-learned tasks, requiring little to no cognitive effort.