Question

Figure shows the position-time graph of an object. Find the ratio of the velocities at $ 5^{th} $ and $ 27^{th} \, $ seconds

• A. $ 1/2 $
• B. $ -1/2 $
• C. $ 1 $
• D. $ -1 $

Answer 1

Answer: (B)

Velocity at $5th$ second will be the velocity in interval $(0-10)\,S$
i.e., $V_{1}=\frac{x_{2}-x_{1}}{t_{2}-t_{1}}$
$=\frac{10-0}{10-0}$

Similarly, velocity at $27th$ sec will be velocity in time interval $(25-30)$
$v_{2}=\frac{x_{4}-x_{3}}{t_{4}-t_{3}}=\frac{0-10}{30-25}=-2$
$\therefore \frac{V_{1}}{V_{2}}=-\frac{1}{2}$