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Physics Class 12th Physics NCERT Exemplar Solutions Class 12th Chapter Four Motion in a Plane

The trajectory of a projectile in an vertical plane is y = ax - bx², where a and b are constants and x & y are respectively the horizontal and vertical distances of the projectile from the point of projection. The angle of projection q and the maximum height attained H are respectively given by

Option 1 -

$t a n^{- 1} α, \frac{4 α^{2}}{β}$

Option 2 -

$t a n^{- 1} α, \frac{α^{2}}{4 β}$

Option 3 -

$t a n^{- 1} β, \frac{α^{2}}{2 β}$

Option 4 -

$t a n^{- 1} (\frac{β}{α}), \frac{α^{2}}{β}$

4 Views | Posted 2 months ago

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1 Answer

Answered by

Payal Gupta | Contributor-Level 10

2 months ago

Correct Option - 2

Detailed Solution:

$y = α x - β x^{2}$

$\Rightarrow \frac{d y}{d x} = α - 2 β x = 0$

$\Rightarrow x = \frac{α}{2 β}$

$y_{m a x} = α \times \frac{α}{2 β} - β \times {(\frac{α}{2 β})}^{2} = \frac{α^{2}}{4 β}$

Range = $2 x = \frac{α}{β} = \frac{2 u^{2} s i n θ . c o s θ}{g}$

On comparing with

y = x tan θ- $\frac{g x^{2}}{2 u^{2} c o s^{2} θ}$

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$| \vec{A} + \vec{B} | = 2 | \vec{A} - \vec{B} |$

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y = x5 (1 - x) = x tanθ $(1 - \frac{x}{R})$

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$s i n θ = \frac{5}{\sqrt[]{26}}, c o s θ = \frac{1}{\sqrt[]{26}}$

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Vishal Baghel

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The trajectory of a projectile in an vertical plane is y = ax - bx², where a and b are constants and x & y are respectively the horizontal and vertical distances of the projectile from the point of projection. The angle of projection q and the maximum height attained H are respectively given by

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The trajectory of a projectile in an vertical plane is y = ax - bx2, where a and b are constants and x & y are respectively the horizontal and vertical distances of the projectile from the point of projection. The angle of projection q and the maximum height attained H are respectively given by

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The trajectory of a projectile in an vertical plane is y = ax - bx², where a and b are constants and x & y are respectively the horizontal and vertical distances of the projectile from the point of projection. The angle of projection q and the maximum height attained H are respectively given by