a large number of bullets are fired ina ll directions
with smae speed v
what is the maximum area on ground on which these bullets will spread
?
1 πv2/g 2 πv4/G2 3) π2v4/g2
4) π2v2/g2
Answers
A large number of bullets are fired in all directions with same speed v. What is the maximum area on ground on which these bullets will spread?
Maximum range of bullet will be at :
This range will be the radius of the circle whose are should be :
This is the radius of the circle (maximum) of bullets falling.
Hence, area of the circle will be :
_____________________
Therefore, the correct answer is [0ptionB].
Answer:
A large number of bullets are fired in all directions with same speed v. What is the maximum area on ground on which these bullets will spread?
\bf\dfrac{\pi v^2}{g^2}
g
2
πv
2
\bf\dfrac{\pi v^4}{g^2}
g
2
πv
4
\bf\dfrac{\pi^2 v^4}{g^2}
g
2
π
2
v
4
\bf\dfrac{\pi^2 v^2}{g^2}
g
2
π
2
v
2
\begin{gathered} \\ \end{gathered}
Maximum range of bullet will be at :
\bf \qquad : \implies \: \theta = 45 \degree:⟹θ=45°
This range will be the radius of the circle whose are should be :
\qquad : \implies \bf \: \pi {r}^{2} :⟹πr
2
\bold{\qquad : \implies \: r = \dfrac{ {u}^{2} \: sin \: 2 \theta}{g} }:⟹r=
g
u
2
sin2θ
This is the radius of the circle (maximum) of bullets falling.
Hence, area of the circle will be :
\qquad : \implies \bf \: a = \pi {r}^{2} :⟹a=πr
2
\qquad \bf: \implies \: a = \pi \: \bigg({ \dfrac{v ^{2} }{g} } \bigg)^{2} :⟹a=π(
g
v
2
)
2
\qquad : \implies \: \bf a = \pi \: \bigg(\dfrac{ {v}^{4} }{ {g}^{2} } \bigg):⟹a=π(
g
2
v
4
)
\qquad : \implies \bf \: a = \dfrac{\pi {v}^{4} }{ {g}^{2} } :⟹a=
g
2
πv
4
\begin{gathered} \\ \end{gathered}
_____________________
Therefore, the correct answer is \bf\dfrac{\pi v^4}{g^2}
g
2
πv
4
[0ptionB].