Find the reading of the spring balance as shown in the figure. Assume that mass $M$ is in equilibrium and the block of mass $2.5 \text{ kg}$ is also in equilibrium. All surfaces are smooth. (Take $g = 10 \text{ m/s}^2$) (in $\text{ N}$)

$A$ solid sphere,a hollow sphere,and a ring are released from the top of a frictionless inclined plane,causing them to slide down the plane. For which object is the acceleration down the plane the maximum?

Two inclined frictionless tracks,one gradual and the other steep,meet at $A$ from where two stones are allowed to slide down from rest,one on each track. Will the stones reach the bottom at the same time? Will they reach there with the same speed? Explain. Given $\theta_{1}=30^{\circ}, \theta_{2}=60^{\circ},$ and $h=10 \; m,$ what are the speeds and times taken by the two stones?

$A$ truck of mass $30,000 \ kg$ moves up an inclined plane of slope $1$ in $100$ at a speed of $30 \ km/h$. The power of the truck is ................. $kW$ (given $g = 10 \ m/s^2$).

As shown in the figure,an iron block $A$ of volume $0.25 \ m^3$ is attached to a spring $S$ of unstretched length $1.0 \ m$ and hanging from the ceiling. The spring gets stretched by $0.2 \ m$. This block is removed and another iron block $B$ of volume $0.75 \ m^3$ is now attached to the same spring and kept on a frictionless inclined plane of $30^{\circ}$ inclination. The distance of the block from the top along the incline at equilibrium is (in $m$)

$A$ football of radius $R$ is kept on a hole of radius $r$ (where the diameter of the hole is $2r$ and $r < R$) made on a plank kept horizontally. One end of the plank is now lifted so that it gets tilted,making an angle $\theta$ with the horizontal as shown in the figure. The maximum value of $\theta$ such that the football does not start rolling down the plank satisfies (figure is schematic and not drawn to scale) -