An effective power of a combination of 5 identical convex lenses which are kept in contact along the principal axis is $$25 \mathrm{D}$$. Focal length of each of the convex lens is:

Given below are two statements :

Statement I : When speed of liquid is zero everywhere, pressure difference at any two points depends on equation $$\mathrm{P}_1-\mathrm{P}_2=\rho g\left(\mathrm{~h}_2-\mathrm{h}_1\right)$$.

Statement II : In ventury tube shown $$2 \mathrm{gh}=v_1^2-v_2^2$$

In the light of the above statements, choose the most appropriate answer from the options given below.

If a rubber ball falls from a height $$h$$ and rebounds upto the height of $$h / 2$$. The percentage loss of total energy of the initial system as well as velocity ball before it strikes the ground, respectively, are :

In an ac circuit, the instantaneous current is zero, when the instantaneous voltage is maximum. In this case, the source may be connected to :

A. pure inductor.

B. pure capacitor.

C. pure resistor.

D. combination of an inductor and capacitor.

Choose the correct answer from the options given below :