Question

A particle experiences a constant acceleration for 20 sec after starting from rest. If it travels a distance $S_{1}$ in the first 10 sec and a distance $S_{2}$ in the next 10 sec, then

• A. $S_{1} = S_{2}$
• B. $S_{1} = S_{2}/3$
• C. $S_{1} = S_{2}/2$
• D. $S_{1} = S_{2}/4$

Answer 1

Answer: (B)

$S_{1} = S_{2}/3$

Answer 2

As$S = ut + \frac{1}{2}at^{2}$ $\therefore$ $S_{1} = \frac{1}{2}a(10)^{2} = 50a$ .....(i)

$As\mspace{6mu}\mspace{6mu} v = u + at$

$\therefore$velocity acquired by particle in 10 sec $v = a \times 10$

For next 10 sec , $S_{2} = (10a) \times 10 + \frac{1}{2}(a) \times (10)^{2}$

$S_{2} = 150a$ .....(ii)

From (i) and (ii) $S_{1} = S_{2}/3$