Assertion : The equation `y= 2x + t` is physical incorrect if x & y are distances and t is time.
Reason : Quantities with different dimension cannot be added or subtracted.

Explanation

To solve the question, we need to analyze the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that the equation \( y = 2x + t \) is physically incorrect if \( x \) and \( y \) are distances and \( t \) is time.

### Step 2: Analyze the Units
- Let’s denote the units:
- \( x \) (distance) has units of meters (m).
- \( y \) (distance) also has units of meters (m).
- \( t \) (time) has units of seconds (s).

### Step 3: Check the Right-Hand Side of the Equation
The right-hand side of the equation is \( 2x + t \):
- The term \( 2x \) has units of meters (m) since \( x \) is in meters.
- The term \( t \) has units of seconds (s).

### Step 4: Identify the Dimensional Inconsistency
In the equation \( y = 2x + t \):
- The left-hand side \( y \) has units of meters (m).
- The right-hand side \( 2x + t \) contains a term with units of meters (m) and a term with units of seconds (s).

Since we cannot add quantities with different dimensions (meters and seconds), the equation is indeed physically incorrect.

### Step 5: Understand the Reason
The reason states that quantities with different dimensions cannot be added or subtracted, which is a true statement.

### Conclusion
Both the assertion and the reason are correct:
- The assertion is correct because the equation mixes dimensions (distance and time).
- The reason is correct as it explains why the assertion holds true.

### Final Answer
Both assertion and reason are correct, and the reason is a correct explanation for the assertion.

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