$A$ body of mass $40 \,g$ is moving with a constant velocity of $2 \,cm/s$ on a horizontal frictionless table. The force on the table is ....... $dyne$.

Write the condition for equilibrium when two forces act on a particle.

$A$ block is placed between two surfaces as shown in the figure. Find the normal reaction at both surfaces. [Assume $g = 10 \ m/s^2$]

Write the similarities and differences between contact force and field force.

$A$ small sphere is hung by a string fixed to a wall as shown in the figure. The sphere is pushed from the wall by a stick. The forces acting on the sphere are as shown. Then,identify the incorrect expression.

Three forces $\vec{P}, \vec{Q},$ and $\vec{R}$ act at a point in a plane. The angles between $\vec{P}$ and $\vec{Q}$,and $\vec{Q}$ and $\vec{R}$ are $150^{\circ}$ and $120^{\circ}$ respectively. What is the ratio of the magnitudes of the forces $\vec{P}, \vec{Q},$ and $\vec{R}$ if the system is in equilibrium?