Answer :
Answer:
[tex]a = 2.6\,\frac{m}{s^{2}}[/tex]
Explanation:
The first box has the following equation of equilibrium:
[tex]\Sigma F = F - f = 0[/tex]
[tex]f = F[/tex]
[tex]f = 48\,N[/tex]
The coefficient of friction is:
[tex]\mu_{k} = \frac{f}{m \cdot g}[/tex]
[tex]\mu_{k} = \frac{48\,N}{(20\,kg)\cdot (9.807\,\frac{m}{s^{2}} )}[/tex]
[tex]\mu_{k} = 0.245[/tex]
There is a net acceleration, when horizontal pushing force is increased:
[tex]\Sigma F = F - f = m\cdot a[/tex]
[tex]a = \frac{F-f}{m}[/tex]
[tex]a = \frac{100\,N-48\,N}{20\,kg}[/tex]
[tex]a = 2.6\,\frac{m}{s^{2}}[/tex]