$A$ liquid drop having surface energy $E$ is spread into $512$ droplets of the same size. The final surface energy of the droplets is (in $E$)

The molar heat capacity of water at constant pressure is $75 \ J \ K^{-1} \ mol^{-1}$. When $1 \ kJ$ of heat is supplied to $100 \ g$ of water,which is free to expand,the increase in temperature of water is ............... $K$.

Two blocks of $7 \ kg$ and $5 \ kg$ are connected by a heavy rope of mass $4 \ kg$. An upward force of $200 \ N$ is applied as shown in the diagram. The tension at the top end of the heavy rope at point $P$ is: $(g = 10 \ m/s^2)$ (in $N$)

The major product in the following reaction is:

Persistent nucellus in the seed is known as

$50 \, g$ of copper is heated to increase its temperature by $10 \, ^\circ C$. If the same quantity of heat is given to $10 \, g$ of water,the rise in its temperature is ........ $^\circ C$ (Specific heat of copper $= 420 \, J \cdot kg^{-1} \cdot ^\circ C^{-1}$,Specific heat of water $= 4200 \, J \cdot kg^{-1} \cdot ^\circ C^{-1}$)