A Machine Gun Is Attached to a Railroad Flatcar That

question 1

Multiple Choice

A machine gun is attached to a railroad flatcar that rolls with negligible friction. If the railroad car has a mass of 6.25 * 10⁴ kg, how many bullets of mass 25 g would have to be fired at 250 m/s off the back to give the railroad car a forward velocity of 0.3 m/s?

• A) 400
• B) 2000
• C) 3000
• D) 5000

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Definitions:

Implicit memory

Memory that enables us to perform tasks without conscious awareness of these previous experiences.

Automatic recall

The ability to retrieve information from memory effortlessly without conscious effort, often seen in well-learned tasks or facts.

Repetition

The act of doing or saying something again and again, often for learning or mastery.

Rheumatoid arthritis

An autoimmune disorder that causes chronic inflammation of joints, leading to pain, swelling, stiffness, and potential loss of function.