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Physics NCERT Exemplar Solutions Class 12th Chapter Nine Physics Class 12th System of Particles and Rotational Motion Physics NCERT Exemplar Solutions Class 12th Chapter Seven

An object is projected in the air with initial velocity u at an angle q. The projectile motion is such that the horizontal range R, in maximum. Another object is projected in the air with a horizontal range half of the range of first object. The initial velocity remains same in both the case. The value of the angle of projection, at which the second object is projected, will be_______degree.

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Vishal Baghel | Contributor-Level 10

2 months ago

$R = \frac{u^{2} s i n (2 \times 45 °)}{g} = \frac{u^{2}}{g}$

$\frac{R}{2} = \frac{u^{2}}{2 g} = \frac{u^{2} s i n 20}{g}$

$s i n 2 θ = \frac{1}{2}$

$\Rightarrow 2 θ = 30 ° \Rightarrow θ = 15 °$

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