• # question_answer A fireman of mass 60 kg slides down a pole. He is pressing the pole with a force of 600 N. The coefficient of friction between the hands and the pole is 0.5, with what acceleration will the fireman slide down? ($g=10\,\,m{{s}^{-2}}$) A)  $1\,\,m{{s}^{-2}}$             B)  $2.5\,\,m{{s}^{-2}}$ C)  $10\,\,m{{s}^{-2}}$                       D)  $5\,\,m{{s}^{-2}}$

Net downward acceleration ${{a}_{d}}=\frac{\text{Weight}-\text{friction force}}{\text{mass}}$ $\Rightarrow$            ${{a}_{d}}=\frac{(mg-\mu R)}{m}$(Area R = normal force)             $=\frac{60\times 10-0.5\times 600}{60}$ $=\frac{300}{60}=5\,\,m{{s}^{-2}}$