A) \[2s\]
B) \[2.5s\]
C) \[3s\]
D) \[1.5s\]
Correct Answer: B
Solution :
Given, \[x=80\,t-16{{t}^{2}}\] On differentiating w.r.t. t, we get \[\frac{dx}{dt}=80-32t\] Since, the stone reaches the maximum height, then velocity will be zero \[\left( ie,\,\,\frac{dx}{dt}=0 \right)\] \[\therefore \] \[80-32t=0\] \[\Rightarrow \] \[t=2.5s\]You need to login to perform this action.
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