If the axes are rotated anticlockwise through an angle $90^{\circ}$, then the equation $x^2=4 \alpha y$ is changed to the equation

• Correct answer
  A

  $y^2=4 a x$
• B

  $x^2=-4 a y$
• C

  $y^2=-4 a x$
• D

  $x^2=4 a y$

Solution

Given, equation of parabola $$ x^2=4 a y $$ Then,
On rotating the axes anti-clockwise through angle $90^{\circ}$, $X$-axis becomes $Y$-axis and $Y$-axis becomes $X$-axis.
Therefore, the equation of new parabola after rotation is $y^2=4 a x$.

Hence, the correct answer is option: 'A'.