Stream line, path line and streak line are identical when the

Stream line, path line and streak line are identical when the Correct Answer Flow is steady

Explanation:

Streamlines:

• Streamlines are a family of curves that are instantaneously tangent to the velocity vector of the flow.
• These show the direction in which a massless fluid element will travel at any point in time.

Streaklines:

• Streaklines are the loci of points of all the fluid particles that have passed continuously through a particular spatial point in the past.
• Dye steadily injected into the fluid at a fixed point extends along a streak line.

Pathlines:

• Pathlines are the trajectories that individual fluid particles follow.
• These can be thought of as "recording" the path of a fluid element in the flow over a certain period.
• The direction the path takes will be determined by the streamlines of the fluid at each moment in time.

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