Two men of unequal masses hold on to the two sections of a light rope passing over a smooth light pulley. Which of the following are possible?

In the system shown in the figure,the acceleration of the $1\,kg$ mass and the tension in the string connecting between $A$ and $B$ is

The same spring is attached to $2 \ kg, 3 \ kg$ and $1 \ kg$ blocks in three different cases as shown in the figure. If $x_1, x_2$ and $x_3$ are the extensions in the spring in these cases,respectively,find the correct relation between them.

$A$ bob of mass $m$ is hanging from a pulley inside a car by a string. The other end of the string is held by a person standing in the car. The car is moving with a constant horizontal acceleration '$a$' as shown in the figure. The other end of the string is pulled with a constant acceleration '$a$' vertically downward. The tension in the string is equal to-

$A$ block of mass $10 \ kg$ is placed on a horizontal frictionless surface and is attached to a cord which passes over two light frictionless pulleys as shown in the figure. The hanging block tied to the other end of the cord is initially at rest $2 \ m$ above the horizontal floor. If the hanging block strikes the floor $2 \ s$ after the system is released,then the weight of the hanging block is ....... $(g=10 \ ms^{-2})$ (in $N$)

Two masses $M_{1}$ and $M_{2}$ are tied together at the two ends of a light inextensible string that passes over a frictionless pulley. When the mass $M_{2}$ is twice that of $M_{1}$,the acceleration of the system is $a_{1}$. When the mass $M_{2}$ is thrice that of $M_{1}$,the acceleration of the system is $a_{2}$. The ratio $\frac{a_{1}}{a_{2}}$ will be: