A ball is projected from the ground at an angle $\theta$ with the horizontal. After $1 \mathrm{s}$ it is moving at an angle $45°$ with the horizontal and after $2 \mathrm{s}$, it is moving horizontally. What is the velocity of projection of the ball?

• A

  $10\sqrt{3}\mathrm{ }\mathrm{m} {\mathrm{s}}^{-1}$
• B

  $20\sqrt{3}\mathrm{ }\mathrm{m} {\mathrm{s}}^{-1}$
• Correct answer
  C

  $10\sqrt{5}\mathrm{ }\mathrm{m }{\mathrm{s}}^{-1}$
• D

  $20\sqrt{2}\mathrm{ }\mathrm{m }{\mathrm{s}}^{-1}$

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