Question

Two bodies move uniformly towards each other. They become $4m$ nearer in every $1$ second. After crossing each other they get $4m$ farther every $10$ second. If their speeds are constant, their values would be

• A. $1.8m{s}^{-1},1.8m{s}^{-1}$
• B. $2.2m{s}^{-1},2.0m{s}^{-1}$
• C. $2.2m{s}^{-1},1.8m{s}^{-1}$
• D. $1.5m{s}^{-1},2.5m{s}^{-1}$

Answer 1

The correct option is C $2.2m{s}^{-1},1.8m{s}^{-1}$

$u_1+u_2=4\cdots \left(i\right)$
$u_1-u_2=0.4\cdots \left(ii\right)$
Adding $\left(i\right)$ and $\left(ii\right)$
$2u_1=4.4$ or $u_1=2.2m{s}^{-1}$
and $u_2=1.8m{s}^{-1}$