A Classical Point Particle Moves Back and Forth with Constant

Multiple Choice

A classical point particle moves back and forth with constant speed between two walls at x = 0 and x = 4 cm.What is the probability density P(x) ?

A) P(x) = 1/(4 cm) ,0 < x < 4 cm P(x) = 0,x < 0 or x > 4 cm
B) P(x) = 1/(4 cm) ,x < 0 or x > 4 cm P(x) = 0,0 < x < 4 cm
C) P(x) = 1/(2 cm) ,0 < x < 4 cm P(x) = 0,x < 0 or x > 4 cm
D) P(x) = 1/(4 cm) ,0 < x < 4 cm P(x) = 1/(2 cm) ,x < 0 or x > 4 cm
E) P(x) = 1/(2 cm) ,0 < x < 4 cm P(x) = 1/(2 cm) ,x < 0 or x > 4 cm