question_answer

A block of mass 2 kg placed on a long frictionless horizontal table is pulled horizontally by a constant force F. It is found to move 10 m in the first two seconds. Find the magnitude of F.

Answer:

Given \[m=2kg,\,\,F=?,\,\,\,\,S=10m,\,\,\,t=2s\] We know, \[F=ma\] How to get a ? Now using, \[s=ut+\frac{1}{2}a{{t}^{2}}\Rightarrow \,\,10=\frac{1}{2}\times a\times {{2}^{2}}\] \[\Rightarrow \,\,a=5\,\,m{{s}^{-2}}\] \[\therefore \,\,\,F=2\times 5=10\,\,N.\]