Question

A block of unknown mass is at rest on a rough, horizontal surface. A horizontal force F is applied to the block. The graph in the figure shows the acceleration of the block with respect to the applied force. The mass of the block is $({\mu }_s={\mu }_k=\mu )$.

• A. $1.0$kg
• B. $0.1$kg
• C. $2.0$kg
• D. $0.2$kg

Answer 1

The correct option is C $2.0$kg

w.k.t force, $F=ma$

where $m-$ mass and $a-$ acceleration

the graph shows that if $F=4N$, $a=0$

It means the limiting value of friction is $4N$

$F_L=4N$

After that we consider a point where $F=8N$, $a=2m/s^2$

$F-F_L=ma$

$8-4=m\left(2\right)$

$m=2kg$