The following plots show variation of velocity ($v$) with time ($t$) of a ball thrown vertically upward, and falling back. Which of the following plots is/are correct?
C only
The question involves identifying the correct velocity-time plot for a ball thrown vertically upwards and falling back down. Here, we analyze the plots based on the motion characteristics of the ball:
- Initially, the ball is thrown upwards with an initial velocity, so the velocity is positive.
- As the ball rises, it slows down due to gravity, and the velocity decreases until it reaches zero at the highest point.
- After reaching the highest point, the ball falls back, gaining speed in the negative direction (downward), so the velocity becomes negative.
Based on these characteristics, the correct plot should start from a positive velocity, decrease to zero, and then continue into negative values.
Let's examine the options:
- Option A: The plot shows a sudden change in velocity, which is incorrect as the velocity decreases gradually.
- Option B: The plot shows velocity decreasing to zero and remaining constant, which is incorrect as velocity cannot remain zero; it should become negative upon descent.
- Option C: This plot starts with a positive velocity, decreases to zero, and becomes negative. This correctly represents the motion of the ball.
- Option D: The plot suggests a continuous increase in velocity, which does not align with the motion described.
- Option E: The plot shows a continuous curve without a distinct transition to and from zero, which is incorrect for this scenario.
Thus, the correct answer is:
C only
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