A Karate Master Strikes a Board with an Initial Velocity

question 52

Multiple Choice

A karate master strikes a board with an initial velocity of 12.0 m/s,decreasing to 3.0 m/s as his hand passes through the board.If the time of contact with the board is 0.002 s,and the mass of the coordinated hand and arm is 1.0 kg,what is the force exerted on the board?

• A)7.5E+3 N
• B)1.8E-2 N
• C)3.0E-2 N
• D)4.5E+3 N
• E)6.0E+3 N

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Definitions:

Rationalization

A mechanism of defense by means of which unacceptable thoughts or impulses are reinterpreted in more acceptable and, thus, less anxiety-arousing terms.

Repression

A defense mechanism where the mind unconsciously blocks unwanted memories, thoughts, or feelings from conscious awareness.

Unconscious Conflict

A psychological struggle within the subconscious mind, stemming from incompatibility between desires or between desires and moral codes, often influencing behavior and emotions.

Transference

In psychotherapy, the process by which patients project feelings and attitudes from past relationships onto their therapist.