What is the normal force on a body of mass $m$ placed on an inclined plane of angle $\theta$?

$A$ 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 wooden blocks are moving on a smooth horizontal surface such that the block of mass $m$ remains stationary with respect to the block of mass $M$ as shown in the figure. The magnitude of force $P$ is:

$A$ block of mass $m_1 = 2\,kg$ on a smooth inclined plane at an angle of $30^\circ$ is connected to a second block of mass $m_2 = 3\,kg$ by a cord passing over a frictionless pulley as shown in the figure. The acceleration of each block is ....... $m/s^2$ (assume $g = 10\,m/s^2$).

$A$ block of mass $m$ is placed on a smooth fixed inclined plane with an angle of inclination of $37^{\circ}$. $A$ horizontal force $F$ is applied to keep the block at rest. Find the value of $F$.

$A$ block '$A$' takes $2\,s$ to slide down a frictionless incline of $30^{\circ}$ and length '$l$',kept inside a lift going up with uniform velocity '$v$'. If the incline is changed to $45^{\circ}$,the time taken by the block to slide down the incline will be approximately $........\,s$.