question_answer

A body starts with a velocity of \[\text{4}0\text{ m}{{\text{s}}^{-\text{1}}}\] and moves with an acceleration of\[\text{1}0\text{ m}{{\text{s}}^{-\text{2}}}\]. Calculate the distance travelled by it in\[\text{1}{{\text{5}}^{\text{th}}}\] second.

Answer:

\[u=40m/s\] \[a=10m{{s}^{-2}}\] Distance travelled by the body in 15th second \[={{S}_{15}}=?\] We know that, \[{{S}_{n}}=u+\frac{a}{2}(2n-1)\] Here n = 15 \[{{S}_{15}}=40+5(29)=40+145=185m\]