iran-konkur 2016 Q162

iran-konkur · Other · konkur-riazi_1395_specialized Not Maths
162- In the figure below, a body is under horizontal force $F_1$ and is at the threshold of motion, and under horizontal force $F_2$ it moves with constant velocity. If the friction forces in these two cases are $f_1$ and $f_2$ respectively, which statement is correct? $(\mu_s > \mu_k)$
[Figure: A block on a rough surface with horizontal force $F$ applied]
  • [(1)] $f_1 > f_2$ , $F_1 > F_2$
  • [(2)] $f_1 > f_2$ , $F_1 = F_2$
  • [(3)] $f_1 = f_2$ , $F_1 < F_2$
  • [(4)] $f_1 = f_2$ , $F_1 = F_2$

\textbf{162-} In the figure below, a body is under horizontal force $F_1$ and is at the threshold of motion, and under horizontal force $F_2$ it moves with constant velocity. If the friction forces in these two cases are $f_1$ and $f_2$ respectively, which statement is correct? $(\mu_s > \mu_k)$

\textit{[Figure: A block on a rough surface with horizontal force $F$ applied]}

\begin{itemize}
    \item[(1)] $f_1 > f_2$ , $F_1 > F_2$
    \item[(2)] $f_1 > f_2$ , $F_1 = F_2$
    \item[(3)] $f_1 = f_2$ , $F_1 < F_2$
    \item[(4)] $f_1 = f_2$ , $F_1 = F_2$
\end{itemize}

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