Question

A rifle shoots a bullet with a muzzle velocity of $500\,m{{s}^{-1}}$ at a small target $50\,m$ away. To hit the target the rifle must be aimed (take$g=10\,m{{s}^{-2}})$

• A. exactly at the target
• B. 10 cm below the target
• C. 10 cm above the target
• D. 5 cm above the target

Answer 1

Answer: (D)

5 cm above the target

Answer 2

Distance $=ut$ $\Rightarrow t=\frac{s}{u}=\frac{50}{500}=0.1\,s$ $\therefore h=0+\frac{1}{2}g\,t^{2}=\frac{1}{2}\times 10\times (0.1)^{2}$ $=0.05\,m=5\,cm$ (above the target)