A man of mass $50 \,kg$ carries a bag of weight $40 \,N$ on his shoulder. The force with which the floor pushes up his feet will be ......... $N$

A block of mass $m$ is placed on a smooth inclined wedge $ABC$ of  inclination $\theta$ as shown in the figure. The wedge is given an acceleration $a$ towards the right. The relation between $a$ and $\theta$ for the block to remain stationary on the wedge is

Four blocks are connected as shown in the fig. on a horizontal frictionless surface of $m_1 = m_2 = m_3 = m_4$ then $T_3/T_4$ will be

$T_1$ and $T_2$ in the given figure are

A book of mass $5 \,kg$ is placed on a table and it is pressed by $10 \,N$ force then normal force exerted by the table on the book is ......... $N$

A block of mass $M$ is at rest on a plane surface inclined at an angle $\theta$ to the horizontal. The magnitude of force exerted by the plane on the block is