Answer:
Angle of projection from the horizontal will be [tex]21.80^{\circ}[/tex]
Explanation:
We have given that range of the projectile is 10 times the height of the projectile
Let the projectile is projected with velocity u at an angle [tex]\Theta[/tex]
Range of the projectile is equal to [tex]R=\frac{u^2sin2\Theta }{g}[/tex]
And height of the projectile is equal to [tex]h=\frac{u^2sin^2\Theta }{2g}[/tex]
Now according to question range is 10 times of height
So [tex]\frac{u^2sin2\Theta }{g}=10\times \frac{u^2sin^2\Theta }{2g}[/tex]
[tex]sin2\Theta =5sin^2\Theta[/tex]
[tex]2sin\Theta cos\Theta =5sin^2\Theta[/tex]
[tex]tan\Theta =\frac{2}{5}=0.4[/tex]
[tex]\Theta =tan^{-1}0.4=21.80^{\circ}[/tex]
So angle of projection from the horizontal will be [tex]21.80^{\circ}[/tex]