A $$12 \mathrm{~V}, 60 \mathrm{~W}$$ lamp is connected to the secondary of a step down transformer, whose primary is connected to ac mains of $$220 \mathrm{~V}$$. Assuming the transformer to be ideal, what is the current in the primary winding ?
Light travels a distance $$\mathrm{x}$$ in time $$t_{1}$$ in air and $$10 \mathrm{x}$$ in time $$t_{2}$$ in another denser medium. What is the critical angle for this medium?
A metal wire has mass $$(0.4 \pm 0.002) ~\mathrm{g}$$, radius $$(0.3 \pm 0.001) ~\mathrm{mm}$$ and length $$(5 \pm 0.02) ~\mathrm{cm}$$. The maximum possible percentage error in the measurement of density will nearly be :
For Young's double slit experiment, two statements are given below :
Statement I : If screen is moved away from the plane of slits, angular separation of the fringes remains constant.
Statement II : If the monochromatic source is replaced by another monochromatic source of larger wavelength, the angular separation of fringes decreases.
In the light of the above statements, choose the correct answer from the options given below :