Question

A stone is thrown horizontally under gravity with a speed of $10$m/sec. Find the radius of curvature of it's trajectory at the end of $3$ sec after motion began.

• A. $10\sqrt{10}$m
• B. $100\sqrt{10}$m
• C. $\sqrt{10}$m
• D. $100$m

Answer 1

The correct option is A $10\sqrt{10}$m

As per given condition of motion the velocity in x direction is $v_x=10m/s$

The velocity in y direction $v_y=gt=10\ast 3=30m/s$

Resultant velocity $v_r=\sqrt{\left(\right(v_x{)}^2+\left(v_y{)}^2\right)}=\sqrt{({10}^2+{30}^2)}=10\sqrt{\left(10\right)}$