Question

Q.):- A body falls freely from rest. It covers as much distance in the last second of its motion as covered in the first three seconds. The body has fallen for a time of
a) 3 s B) 5 s C) 7 s D) 9 s

Answer 1

Dear Student,
$$\begin{gathered} Accordingtoquestion \\ dis\tan ceinfirst3s=\frac{1}{2}\times 10\times 3^2=45m \\ andletitfallsforts \\ thendis\tan ceinlastseconds=0+\frac{g}{2}\left(2t-1\right)=45 \\ t=\frac{10}{2}=5s \end{gathered}$$
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