Q78 / 90 · JEE Main 2024 (04 Apr Shift 1) · Physics
The co-ordinates of a particle moving in $x-y$ plane are given by : $x=2+4 \mathrm{t}, y=3 \mathrm{t}+8 \mathrm{t}^2$.
The motion of the particle is :
- Correct answerAuniformly accelerated having motion along a parabolic path.
- Buniform motion along a straight line.
- Cuniformly accelerated having motion along a straight line.
- Dnon-uniformly accelerated.
Solution
$\begin{aligned}
& x=2+4 t \\
& \frac{d x}{d t}=v_x=4 \\
& \frac{d v_x}{d t}=a_x=0 \\
& y=3 t+8 t^2 \\
& \frac{d y}{d t}=v_y=3+16 t \\
& \frac{d v_y}{d t}=a_y=16
\end{aligned}$
the motion will be uniformly accelerated motion.
For path
$\begin{aligned}
& \mathrm{x}=2+4 \mathrm{t} \\
& \frac{(\mathrm{x}-2)}{4}=\mathrm{t}
\end{aligned}$
Put this value of $t$ is equation of $y$ $y=3\left(\frac{x-2}{4}\right)+8\left(\frac{x-2}{4}\right)^2$ this is a quadratic equation so path will be parabola.
Put this value of $t$ is equation of $y$ $y=3\left(\frac{x-2}{4}\right)+8\left(\frac{x-2}{4}\right)^2$ this is a quadratic equation so path will be parabola.
Hence, the correct answer is option: 'A'.