MCQ
A particle is moving in a straight line with initial velocity and uniform acceleration $a$. If the sum of the distance travelled in $t^{\text {th }}$ and $( t +1)^{ th }$ seconds is $100 cm$, then its velocity after $t$ seconds, in $.........cm / s$, is
  • A
    $80$
  • $50$
  • C
    $20$
  • D
    $30$

Answer

Correct option: B.
$50$
b
(b) 

Sum of distance travelled in $t^{t h}$ and $(t+1)^{t h}$ seconds is $100 cm$

$u+\frac{a}{2}(2 t-1)+u+\frac{a}{2}(2(t+1)-1)=100$

$2 u+2 a t=100$

$u+a t=100 / 2$

$\Rightarrow v=50 cm / s$

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