Assertion : The `upsilon-t` graph perpendicular to time axis is not possible in particle.
Reason : Infinite acceleration cannot be realised in particle.

Options

A. If both Assertion and Reason are correct and Reason is the correct explanation of assertion.
B. If both Assertion and Reason are correct but Reason in not the correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If Assertion is false but Reason is true.

Explanation

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

### Step 1: Understand the Assertion
The assertion states that a velocity-time (v-t) graph that is perpendicular to the time axis is not possible for a particle.

### Step 2: Analyze the v-t Graph
In a v-t graph, the x-axis represents time (t) and the y-axis represents velocity (v). If the graph is perpendicular to the time axis, it means that for a specific instant of time, there would be multiple values of velocity. This implies that the particle could be moving at different velocities at the same moment, which is physically impossible. Hence, the assertion is true.

### Step 3: Understand the Reason
The reason states that infinite acceleration cannot be realized in a particle.

### Step 4: Relate Acceleration to the v-t Graph
Acceleration (a) is defined as the rate of change of velocity with respect to time. Mathematically, it is given by:
\[ a = \frac{dv}{dt} \]
If the v-t graph is perpendicular to the time axis, it implies that the change in velocity (dv) is occurring instantaneously with no change in time (dt = 0). This would lead to an infinite value for acceleration, which is not physically realizable. Therefore, the reason is also true.

### Step 5: Conclusion
Both the assertion and the reason are correct, and the reason provides a valid explanation for the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer
Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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