STATEMENT-1: Potential energy has a minimum at the position of stable equilibrium.
STATEMENT-2: Mechanical energy of a system is always positive
STATEMENT 3-: Work done by the friction may be positive
identify the correct combination of true (T) and false (F) of the given three statements

Options

A. T F T
B. T T T
C. F F T
D. F F F

Answer

To solve the question, we need to evaluate each of the three statements provided and determine whether they are true (T) or false (F).

### Step 1: Evaluate Statement 1
**Statement 1:** Potential energy has a minimum at the position of stable equilibrium.

- **Analysis:** In physics, a stable equilibrium is characterized by a minimum in potential energy. When a system is at a stable equilibrium, any small displacement from this position will result in forces that tend to restore the system back to equilibrium. Therefore, this statement is **True (T)**.

### Step 2: Evaluate Statement 2
**Statement 2:** Mechanical energy of a system is always positive.

- **Analysis:** Mechanical energy is defined as the sum of kinetic energy (KE) and potential energy (PE). While kinetic energy is always positive (since it is a function of the square of velocity), potential energy can be negative, zero, or positive depending on the reference point chosen. For example, if the potential energy is -10 J and the kinetic energy is +5 J, the total mechanical energy would be -5 J. Therefore, this statement is **False (F)**.

### Step 3: Evaluate Statement 3
**Statement 3:** Work done by friction may be positive.

- **Analysis:** Work done by friction is typically negative because friction opposes motion. However, if the direction of friction coincides with the direction of displacement (which is not common but can happen in certain scenarios, such as when an object is moving in a circular path and friction acts in the direction of the motion), the work done can be positive. Thus, this statement is **True (T)**.

### Conclusion
Now, we can summarize the evaluations:
- Statement 1: True (T)
- Statement 2: False (F)
- Statement 3: True (T)

The correct combination of the statements is **T, F, T**.

### Final Answer
The correct combination of true (T) and false (F) for the given three statements is: **T, F, T**.

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