A 7000-Kg Coal Car of a Train Coasts at 7

question 47

Multiple Choice

A 7000-kg coal car of a train coasts at 7.0 m/s on a frictionless track when a 3000-kg load of coal is dropped vertically onto the car.The coal car's speed after the coal is added is

• A)2.1 m/s
• B)3.0 m/s
• C)4.9 m/s
• D)7.0 m/s
• E)16 m/s

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Definitions:

45-degree Angle

A precise measurement where two lines or surfaces meet to form an angle that is half the size of a right angle, often used in geometry and various applications to denote a moderate inclination.

15-degree Angle

A measure of rotation that equals one-sixteenth of a complete circle's rotation; it's a small acute angle commonly used in geometry.

60-degree Angle

An angle measuring 60 degrees, often associated with equilateral triangles where all three interior angles are equal.

Productive Cough

A cough that expels mucus or phlegm from the respiratory tract, assisting in clearing the airways.