Question

The system starts from rest and $A$ attained a velocity of $5m/s$ after it has moved $5m$ towards right. Assuming the arrangement to be frictionless every where and pulley & strings to be light, if the constant force $F$ applied on $A$ then find the value of $F$.

• A. $75$
• B. $85$
• C. $95$
• D. $100$

Answer 1

The correct option is A $75$

$Given:$ Final velocity$=5m/s$ ; inital velocity$=0m/s$; Distance$=5m$

$Solution:$ We know that,

$a=\frac{v^2}{2_s}=\frac{25}{10}=2.5m/s^2$

For$6kg:-F-2T=6a$ $........\left(1\right)$

For$2kg:-2g=2\left(2a\right)$$.........\left(2\right)$

From (1) and (2) $F=75N$

$\text{So, the correct option:A}$