Question

A particle start moving along a straight line path with a velocity $10m{s}^{-1}$. After $5s$, the distance of the particle from the starting point is $50m$. Which of the following statement about the nature of motion of the particle are correct?

• A. The body may be speeding up with constant positive acceleration.
• B. The motion may be moving with constant velocity.
• C. The body may have constant negative acceleration.
• D. The motion may be first acceleration and then retarded.

Answer 1

Answer: (B), (C), (D)

The correct options are
B The motion may be moving with constant velocity.
C The body may have constant negative acceleration.
D The motion may be first acceleration and then retarded.

$\to$ If Pt $B$ moving with constant velocity,

$S=ut+\frac{1}{2}{at}^2$

$=10\times 5$

$=50m$

$\to$ If the final position Ps $50$m behind its initial position,

$S=ut+\frac{1}{2}{at}^2$

$-50=10\times 5+\frac{1}{2}a\times 25$

$\Rightarrow a=-8$

$\therefore$ constant retardation.

$\to$ A combination of acceleration and retardation can also satisfy the given condition.