Question

A circular disc of radius r = 5 m is rotating in horizontal plane about y-axis. y-axis a vertical axis passing through the centre of disc and x-z is the horizontal plane at ground. The height of disc above ground is h = 5 m. Small particles are ejecting from disc in horizontal direction with speed 12 m/s from the circumference of disc then the distance of these particles from origin when they hits x – z plane is –

• A. 5 m
• B. 12 m
• C. 13 m
• D. None of these

Answer 1

Answer: (C)

13 m

Answer 2

R = $u\sqrt{\frac{2h}{g}}$= $12\sqrt{\frac{2 \times 5}{10}}$ = 12 m

\ Distance from origin = $\sqrt{5^{2} + (12)^{2}}$= 13 m