question_answer

A body is projected vertically up and the total distance travelled by it is s. What is the total time of its flight?

Answer:

Total distance travelled by the body \[s=2\times \max imum\,\,height\] \[s=2\times \frac{{{u}^{2}}}{2g}\Rightarrow s=\frac{{{u}^{2}}}{g}\Rightarrow {{u}^{2}}=g\,\,s\] we know that time of flight\[T=\frac{2u}{g}\] \[\Rightarrow {{T}^{2}}=\frac{4{{u}^{2}}}{{{g}^{2}}}=\frac{4\times gs}{{{g}^{2}}}=\frac{4s}{g}\therefore T=\sqrt{\frac{4s}{g}}\]