Question

Consider the following Statements [1] and [2].
Statement [1]: The Eulerian study focuses attention on individual particle and its motion is observed as a function of time.
Statement [2]: The Lagrangian study focuses attention on the motion of the particles passing through an identified point.
Which one of the following options identifies the correctness of the given statements?
 

• A. Both [1] and [2] are correct.
• B. Both [1] and [2] are NOT correct.
• C. [1] is correct, but [2] is NOT correct.
• D. [1] is NOT correct, but [2] is correct.

Hint:

The Eulerian method observes flow properties at fixed locations in space, while the Lagrangian method tracks individual particles and their motion through space.

Answer 1

The Correct Option is B

The Eulerian and Lagrangian methods are two fundamental approaches in fluid mechanics for describing the motion of fluid particles.
- Eulerian Method: This method focuses on observing the fluid at fixed points in space. In other words, the Eulerian study looks at the velocity field at specific locations, as a function of time. It does not track individual particles; rather, it focuses on how the flow characteristics change at fixed points in space. 
Therefore, Statement [1] is incorrect, because it wrongly describes the Eulerian study as focusing on individual particles and their motion as a function of time.
- Lagrangian Method: The Lagrangian study, on the other hand, follows individual fluid particles as they move through space. This method tracks the motion of particles from a fixed perspective, which means it looks at the movement of fluid particles as they pass through identified points. Therefore, Statement [2] is also incorrect, as it wrongly describes the Lagrangian method as focusing on the motion of particles passing through a specific point, which is not its primary focus. The Lagrangian approach follows individual particles along their entire path, rather than observing the flow at fixed points.
Thus, the correct answer is (B) Both [1] and [2] are NOT correct.