For a moving body at any instant of time

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Question

$(A)$ Suppose throwing a ball vertically up. At the highest point. It is at momentary rest $( V = O )$ i but acceleration $g$ still acts downwards. So

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If displacement, velocity and acceleration at that instant are known, we can find the displacement at any given time in future

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$(A)$ Suppose throwing a ball vertically up. At the highest point. It is at momentary rest $( V = O )$ i but acceleration $g$ still acts downwards. So, (A) is incorrect.

$(B)$ A slowing body has positive retardation.

$(C)$ Distance travelled is always positive, irrespective its motion.

$(D)$ From second law of kinematics,

$x=x_0+u t+\frac{1}{2} a^2$

By knowing $u , a$ and $x _0$ at instant $t =0$ we can determine $x$ at any $t$.

Graph	Characteristics
$(A)$	$(i)$ has $v > 0$ and $a < 0$ throughout
$(B)$	$(ii)$ has $x > 0,$ throughout and has a point with $v = 0$ and a point with $a = 0$
$(C)$	$(iii)$ has a point with zero displacement for $t > 0$
$(D)$	$(iv)$ has $v < 0$ and $a > 0$

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