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Motion in a Plane

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Question : 29 of 32
Marks: +1, -0
A bullet fired at an angle of 30° with the horizontal hits the ground 3.0 km away. By adjusting its angle of projection, can one hope to hit a target 5.0 km away? Assume the muzzle speed to be fixed, and neglect air resistance.
Solution:  
Horizontal range, R=u2sin2θgR=\frac{u^{2} \sin 2\theta}{g} or 3=u2sin60g=u2g323=\frac{u^{2} \sin 60^{\circ}}{g}=\frac{u^{2}}{g} \frac{\sqrt{3}}{2}
nce the muzzle velocity is fixed, therefore, Maximum horizontal range,
Rmax=u2g=23=3.464mR_{\text{max}}=\frac{u^{2}}{g}=2\sqrt{3}=3.464\text{m}
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