question_answer

A block of mass 10 kg is placed on a rough horizontal surface whose coefficient of friction is 0.5. If a horizontal force of 100 N is applied on it, then acceleration of block will be:

A) \[10\text{ }m/{{s}^{2}}\]       

B) \[5\,m/{{s}^{2}}\]

C) \[15\text{ }m/{{s}^{2}}\]      

D) \[~0.5\,m/{{s}^{2}}\]

Correct Answer: B

Solution :

 Force that produces acceleration is \[F=F-\mu R\] Given, \[F=100\,N,\] \[F=\mu R=0.5\times 10\times 10\] \[\therefore \] \[F=100-50=50\,N\] Also, acceleration\[=\frac{F}{m}=\frac{50}{10}=5\,m/{{s}^{2}}\]