Physics

In a Young's double slit experiment, a student observes 8 fringes in a certain segment of screen when a monochromatic light of 600nm wavelength is used. If the wavelength of light is changed to 400nm, then the number of fringes he would observe in the same region of the screen is:

An electric lift with a maximum load of 2000Kg (lift + passenger) is moving up with a constant speed $1.5{\mathrm{m}\mathrm{s}}^{-1}$ ${}^{}$ . The frictional force opposing the motion is 2000N${}^{}$ . The minimum power delivered by the motor to lift in watts is : $\left(\mathrm{g}=10{\mathrm{m}\mathrm{s}}^{-2}\right)$

Match List- I with Li

Choose the correct answer from the options given below:

a)-(iv),
(b)-(iii), (c) - (ii), (d) - (i)

Two objects of mass $10\mathrm{k}\mathrm{g}$ and $20\mathrm{k}\mathrm{g}$ respectively are connected to the two ends of a rigid rod of length 10 $\mathrm{m}$ with negligible mass. The distance of the centre of mass of the system from the $10\mathrm{k}\mathrm{g}$  mass is :

In half wave rectification, if the input frequency is $60\mathrm{H}\mathrm{z}$ , then the output frequency would be :

The energy that will be ideally radiated by a $100\mathrm{k}\mathrm{W}$  transmitter in 1 hour is

If a soap bubble expands, the pressure inside the bubble :

The dimensions $\left[{\mathrm{M}\mathrm{L}\mathrm{T}}^{-2}{\mathrm{A}}^{-2}\right]$ $\left[{}^{}{}^{}\right]$ belong to the:

The angle between the electric lines of forces and the equipotential surface is

How can you tell whether a medium has low or high index of refraction?