A) ut
B) \[\frac{1}{2}g{{t}^{2}}\]
C) \[ut-\frac{1}{2}g{{t}^{2}}\]
D) \[(u+gt)t\]
Correct Answer: B
Solution :
Let time of flight be T then \[T=\frac{u}{g}\] Let h be the distance covered during last 't' second of its ascent Velocity at point \[B={{v}_{B}}=u-g(T-t)\] \[=u-g\left( \frac{u}{g}-t \right)=gt\] \[\Rightarrow \] \[h={{v}_{B}}t-\frac{1}{2}g{{t}^{2}}\] \[\Rightarrow \] \[h=g{{t}^{2}}-\frac{1}{2}g{{t}^{2}}=\frac{1}{2}g{{t}^{2}}\]You need to login to perform this action.
You will be redirected in
3 sec