Question

The figure shows displacement of particle going along the $x$-axis as a function of time. The force acting on the particle is zero in the region :

• A. AB
• B. BC
• C. CD
• D. DE

Answer 1

Answer: (A), (C)

The correct options are
A AB
C CD

In the graph $x$ vs $t$, there are two linear region, $AB$ and $CD$,
It means that in these regions motion of the particles can be defined as equation of line, for which $X$ co-ordinate is time and $Y$ co-ordinate is displacement $x$ and some constant $c$ as,
$x=m\times t+c$
And force on a particle is defined as,
$F=ma=m\frac{d^{2}x}{d{t}^2}$
$\frac{d^{2}x}{d{t}^2}=0$, during path $AB$ and $CD$, other paths are non linear means, $\frac{d^{2}x}{d{t}^2}\ne 0$..
Option A and C are correct.