Question

For the given diagram for what maximum value of force both block will move together?

• A. $150\text{N}$
• B. $200\text{N}$
• C. $\frac{400}{3}\text{N}$
• D. $80\text{N}$

Answer 1

The correct option is C $\frac{400}{3}\text{N}$

Net acceleration of system
$a=\frac{F}{50},\text{Maximum friction at contact}{f}_L=\left(0.4\right)\left(200\right)=80\text{N}$

$F-80=20a$
$F-80=20\left(\frac{F}{50}\right)$
$\frac{3F}{5}=80$
$F=\frac{400}{3}\text{N}$