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Grade 11Mechanics

A bullet fired from a point on horizontal ground at an angle 30 degree with the horizontal hits the ground 3 km away. By adjusting the angle of projectio, can one hope to hit a target 5 km away?

Pragya bharti

9 Years agoGrade 11

1 Answer

Piyush Kumar Behera

9 Years ago

Solution:

Given that:

Range, R = 3 km

Angle of projection, θ = 30°

Acceleration due to gravity, g = 10 m/s

Horizontal range for the projection velocity u , is given by the relation:

u²/g=2 $\sqrt{3 }$

The maximum range (R ) is achieved by the bullet when it is fired at an angle of 45° with the horizontal, that is,

R_max=u²/g

On comparing equations (i) and (ii), we get:

R_max=3 $\sqrt{3 }$ =3.46km

Hence, the bullet will not hit a target 5 km away

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