Consider the following statements about the blocks shown in the diagram that are being pushed by a constant force $F$ on a frictionless table:
$A.$ All blocks move with the same acceleration.
$B.$ The net force on each block is the same.
Which of these statements is/are correct?

$A$ mass $m$ is suspended by two strings $T_1$ and $T_2$ as shown in the figure. Calculate the tensions $T_1$ and $T_2$.

$A$ uniform sphere of weight $W$ and radius $R = 3\,m$ is held by a string of length $L = 2\,m$ attached to a frictionless wall as shown in the figure. The tension in the string is:

$A$ flexible chain of mass $m$ hangs between two fixed points at the same level. The inclination of the chain with the horizontal at the two points of support is $30^{\circ}$. Considering the equilibrium of each half of the chain, the tension of the chain at the lowest point is . . . . . . .

Explain the main types of forces with suitable examples.

Ten one-rupee coins are placed on top of each other on a table. Each coin has a mass $m$. Give the magnitude and direction of:
$(a)$ The force on the $7^{\text{th}}$ coin (counted from the bottom) due to all the coins on its top.
$(b)$ The force on the $7^{\text{th}}$ coin by the $8^{\text{th}}$ coin.
$(c)$ The reaction of the $6^{\text{th}}$ coin on the $7^{\text{th}}$ coin.