Question

An arrow is projected into air. Its time of flight is 5 s and range 200 m. What is the maximum height reached by it? (Take g = 10 m s^-2)

• A. 31.25 m
• B. 24.5 m
• C. 18.25 m
• D. 46.75 m

Answer 1

Answer: (A)

Given, $5=\frac{2u sin \theta}{g}$ or $\frac{u sin \theta }{2g}=\frac{5}{2}$
Maximum height $=\frac{u^{2} sin^{2} \theta}{2g}=\frac{g}{2}\times\left(\frac{u^{2} sin^{2} \theta}{g^{2}}\right)$
$\frac{g}{2}\times\left(\frac{5}{2}\right)^{2}=\frac{10}{2}\times\frac{25}{4}=31.25$m