Question

For the arrangement shown in the figure, the tension in the string is given by $(sin{37}^{\circ }=\frac{3}{5})$. Take $g=10m{s}^{-2}$

• A. $30N$
• B. $40N$
  
• C. $60N$
• D. $30N$

Answer 1

The correct option is B $40N$


Net pulling force on the system $F=10gsin{37}^{\circ }-4g=20N$
maximum force of friction
$f_{max}=\mu \text{mg cos}{37}^{\circ }$
$=0.7\times 10\times 10\times \frac{4}{5}=56N$
Since $F<f_{max}$, system will not move. Equilibrium of $4kg$ gives $T=40N$.