List of top Physics Questions on Youngs double slit experiment asked in MHT CET

In Young's double slit experiment, we get 15 fringes per cm on the screen, using light of wavelength 5600 \AA. For the same setting, how many fringes per cm will be obtained with light of wavelength 7000 \AA?
In Young's double slit experiment, we get 15 fringes per cm on the screen, using light of wavelength 5600 Ã…. For the same setting, how many fringes per cm will be obtained with light of wavelength 7000 Ã…?
In Young's double slit experiment, if the distance between the slits is doubled while keeping the wavelength and the distance to the screen constant, the fringe spacing will: