A point mass $m$ is suspended from a light thread of length $l,$ fixed at $O,$ is whirled in a horizontal circle at constant speed as shown. From your point of view, stationary with respect to the mass, the forces on the mass are
When $F =2 N$, the frictional force between 5 $kg$ block and ground is $..........\,N$
A person in an elevator accelerating upwards with an acceleration of $2\,ms^{-2}$ , tosses a coin vertically upwards with a speed of $20\,ms^{-1}$ . After how much time will the coin fall back into his hand ? $(g = 10\,m s^{-2})$
What should be the minimum force $P$ to be applied to the string so that block of mass $m$ just begins to move up the frictionless plane.
A block of mass $m$ lying on a rough horizontal plane is acted upon by a horizontal force $P$ and another force $Q$ inclined an at an angle $\theta$ to the vertical. The minimum value of coefficient of friction between the block and the surface for which the block will remain in equilibrium is :
Two blocks are connected by a spring. The combination is suspended, at rest, from a string attatched to the ceiling, as shown in the figure. The string breaks suddenly. Immediately after the string breaks, what is the initial downward acceleration of the upper block of mass $2\,m$ ?