### Laws of Motion

goals
A lead block is suspended from your hand by a string. The reaction due to the force of gravity on the block is the force exerted by :
An object of mass $2\ kg$ is placed in a frame $(s_{1})$ moving with velocity $10\vec {i} + 5\vec {j} m/s$ and having acceleration $5\vec {i} + 10\vec {j} m/s^{2}$. This object is also seen by an observer standing in frame $(s_{2})$ moving with velocity $5\vec {i} + 10\vec {j} m/s$. The net force acting on object with respect to $s_{2}$ frame is
During a planned manoeuvre in a space flight, a free-floating astronaut A pushes another free-floating astronaut B, the mass of A being greater than that of B. Then, the magnitude of the force exerted by astronaut A on astronaut B is
In the above problem, during a push
Three masses m, m and 2 m are held stationary as shown in the figure with all the strings taut. Now, the mass 2 m is released and it starts falling vertically downward.

Velocity of masses m at the instant 2m touches the gound is
What is net Force?