Given, initial height, yi=375m Final height, yf=0m Initial velocity, vi=100m∕s Initial horizontal range, xi=0 Angle of projection, θ=30∘ Now, yf=yi+vit−‌
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gt2 yf=yi+vigsin‌θt−‌
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gt2 ‌0=375+(100×sin‌30∘)t−‌
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×9.8t2 ‌0=375+50t−4.9t2 ‌‌‌⇒4.9t2−50t−375=0 On solving, we get t1=15.22s‌ and ‌t2=−5.02s Now time cannot be negative hence, t=15.22s Thus horizontal rang, R=vt‌cos‌θ‌t ‌=100×cos‌30∘×15.22 ‌=100×‌
