Question

A block of mass $2kg$ placed on a long place on a long friction less horizontal tab;e is pulled horizontally by a constant force $F.$ it is found to move $10m$ in the first two second . Find the magnitude of $F.$

• A. $7N$
• B. $10N$
• C. $12N$
• D. $8N$

Answer 1

The correct option is B $10N$

$\begin{array}{c}m=2kg\\ S=10m\\ Let,accelaration=a\\ Initialvelocityu=0\\ S=ut+\frac{1}{2}a{t}^2\\ \Rightarrow 10=\frac{1}{2}a\left(2^2\right)\\ \Rightarrow 10=2a\\ \Rightarrow a=5m/s^2\\ Now,\\ Force:F=ma\\ =2\times 5=10\\ Hence,optionBiscorrectanswer.\end{array}$