Question

Consider the following Statements [1] and [2].
Statement [1]: The Eulerian study focusses attention on individual particle and its motion is observed as a function of time.
Statement [2]: The Lagrangian study focusses 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:

Remember: Eulerian = fixed point in space, observe field variables with time. Lagrangian = track individual particles, follow their trajectories.

Answer 1

The Correct Option is B

Step 1: Recall Eulerian approach.
- In the Eulerian method, the focus is on a \emph{fixed point in space}. - The fluid motion is described by monitoring how velocity, pressure, etc. change with time at that point. - It does \emph{not} follow individual particles. Thus, Statement [1] is incorrect.

Step 2: Recall Lagrangian approach.
- In the Lagrangian method, we track the motion of \emph{individual particles} from their initial positions as time evolves. - It does not focus on particles crossing a fixed point in space. Thus, Statement [2] is also incorrect.

Step 3: Conclusion.
Both [1] and [2] are wrong. Final Answer:
\[ \boxed{\text{Both [1] and [2] are NOT correct.}} \]