Light of wavelength $$\lambda$$ strikes a photoelectric surface and electrons are ejected with kinetic energy $$K$$. If $$K$$ is to be increased to exactly twice its original value, the wavelength must be changed to $$\lambda^{\prime}$$, such that
When in $$p$$-$$n$$ junction diode, $$p$$ is connected to the positive terminal and $$n$$ is connected to the negative terminal, then it is
If an object of height $$6 \mathrm{~cm}$$ is viewed through a liquid of refractive index $$\frac{4}{3}$$ vertically at a depth of $$10 \mathrm{~cm}$$. Then what will be its apparent height and apparent distance from the surface of liquid.
The half-life period of a radioactive element $$x$$ is same as the mean life time of another radioactive element $$y$$. Initially, both of them have the same number of atoms. Then,