A soap bubble of radius '$$R$$' is blown. After heating a solution, a second bubble of radius '$$2 \mathrm{R}$$' is blown. The work required to blow the $$2^{\text {nd }}$$ bubble in comparison to that required for the $$1^{\text {st }}$$ bubble is
In a transistor, in common emitter configuration, the ratio of power gain to voltage gain is
A galvanometer of resistance $$20 ~\Omega$$ gives a deflection of 5 divisions when $$1 \mathrm{~mA}$$ current flows through it. The galvanometer scale has 50 divisions. To convert the galvanometer into a voltmeter of range 25 volt, we should connect a resistance of
The equation of simple harmonic progressive wave is given by $$y=a \sin 2 \pi(b t-c x)$$. The maximum particle velocity will be half the wave velocity, if $$\mathrm{c}=$$