Starting from the origin at time $t=0$, with initial velocity
$5 \hat{j} \mathrm{~ms}^{-1}$, a particle moves in the $x-y$ plane with a constant
acceleration of $(10 \hat{i}+4 \hat{j}) \mathrm{ms}^{-2}$. At time $t$, its coordiantes
are $\left(20 \mathrm{~m}, y_{0} \mathrm{~m}\right)$. The values of $t$ and $y_{0}$ are, respectively:
Correct Option: 1
(1) Given: $\vec{u}=5 \hat{j} \mathrm{~m} / \mathrm{s}$
Acceleration, $\vec{a}=10 \hat{i}+4 \hat{j}$ and
final coordinate $\left(20, y_{0}\right)$ in time $t$.
$S_{x}=u_{x} t+\frac{1}{2} a_{x} t^{2}$ $\left[\because u_{x}=0\right]$
$\Rightarrow 20=0+\frac{1}{2} \times 10 \times t^{2} \Rightarrow t=2 \mathrm{~s}$
$S_{y}=u_{y} \times t+\frac{1}{2} a_{y} t^{2}$
$y_{0}=5 \times 2+\frac{1}{2} \times 4 \times 2^{2}=18 \mathrm{~m}$
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