Question

In the figure shown, both the blocks are of equal mass of $10kg$ and $F=300N$. Find the value of tension $T$ in the string in between the blocks.

• A. $100N$
• B. $150N$
• C. $200N$
• D. $250N$

Answer 1

The correct option is B $150N$

Considering the blocks to form a system, the force equation for this system can be given as
$F-20g\sin {30}^{\circ }=20a$
Here, $F>20gsin{30}^{\circ }$ so, the blocks will slide up the plane.
$⟹300-20\times 10\times \frac{1}{2}=20a$
$⟹a=10m/s^2--\left(i\right)$

FBD of block $B$

From the FBD, we can write the force equation as
$F-T-10g\sin {30}^{\circ }=10a--\left(ii\right)$

Using equation $\left(i\right)$ in $\left(ii\right)$, we get
$300-T-50=10\times 10$
$\therefore T=150N$