A large open tank containing water has two holes to its wall. A square hole of side $a$ is made at a depth $$y$$ and a circular hole of radius $$r$$ is made at a depth $$16 y$$ from the surface of water. If equal amount of water comes out through both the holes per second, then the relation between $$r$$ and $$a$$ will be

Refractive index of the medium is $$\mu$$ and wavelength is $$\lambda$$, then which of the following proportionality relation is correct?

$$A$$ transistor has a voltage gain $$A$$. If the amount $$\beta A$$ of its output is applied to the input of the transistor, then the transistor becomes oscillator, when

A spherical rubber balloon carries a charge, uniformly distributed over the surface. As the balloon is blown up and increases in size, the total electric flux coming out of the surface