Kinematics Question 678
Question: A large number of bullets are fired in all directions with same speed $ v $ . What is the maximum area on the ground on which these bullets will spread
Options:
A) $ \pi \frac{v^{2}}{g} $
B) $ \pi \frac{v^{4}}{g^{2}} $
C) $ {{\pi }^{2}}\frac{v^{4}}{g^{2}} $
D) $ {{\pi }^{2}}\frac{v^{2}}{g^{2}} $
Show Answer
Answer:
Correct Answer: B
Solution:
[b] Area in which bullet will spread = $ \pi r^{2} $
For maximum area, $ r={R _{\max }}=\frac{v^{2}}{g}[\text{when }\theta =45{}^\circ ] $
Maximum area $ \pi \ R _{\max }^{2}=\pi {{( \frac{v^{2}}{g} )}^{2}}=\frac{\pi v^{4}}{g^{2}} $
