A force $\vec{F}=\hat{i}+4 \hat{j}$ acts on block shown. The force of friction acting on the block is
The $50\, kg$ homogeneous smooth sphere rests on the $30^o$ incline $A$ and bears against the smooth vertical wall $B$. Calculate the contact force at $A$
A block placed on a rough inclined plane of inclination $\left(\theta=30^{\circ}\right)$ can just be pushed upwards by applying a force " $F$ " as shown. If the angle of inclination of the inclined plane is increased to $\left(\theta=60^{\circ}\right)$, the same block can just be prevented from sliding down by application of a force of same magnitude. The coefficient of friction between the block and the inclined plane is
A body of mass $8\,kg$ is hanging another body of mass $12\,kg$. The combination is being pulled by a string $T _2$ will be respectively: (use $g =9.8\,m / s ^2$ )
A balloon with mass $'m'$ is descending down with an acceleration $'a'$ (where $a < g$ ). How much mass should be removed from it so that it starts moving up with an acceleration $'a'$ ?