A. black
B. purple
C. green
D. no scientific reasoning available
Related Mcqs:
- In a photoelectric effect monochromatic light is incident on a metal surface. If the incident light of twice the intensity but of same wavelength the kinetic energy of the emitted electron_______________?
A. Becomes double
B. Remains same
C. Becomes half
D. First increases then decrease because of the curvilinear graph - Which one of the following is nearly monochromatic light ?
A. light form fluorescent tube
B. light form neon lamp
C. light form sodium lamp
D. light form simple lamp - A point where the incident parallel rays of light converge or appear to diverge after passing through a lens is called______________?
A. center of curvature
B. focus
C. optical center
D. aperture - Gives the definition of metre in terms of wavelength of red cadmium light ___________________?
A. Newton
B. Einstein
C. Michelson
D. Galileo - The blue colour of the sky is due to___________________?
A. diffraction
B. reflection
C. polarization
D. scattering - A point source of light placed in a homogeneous medium gives rise to ___________________?
A. a cylindrical wave front
B. an elliptical wave front
C. a spherical wave front
D. a plane wave front - When one mirror of a Michelson Interferometer is moved a distance of 0.5 mm we observe 2000 fringes. What will be wavelength of light used ?
A. 5000 nm
B. 5000A
C. 500m
D. 2000um - Two sources of light are coherent if they emit rays of_______________?
A. same wavelength
B. same amplitude of vibration
C. same wave length with constant phase difference
D. same amplitude and wavelength - The velocity of light was determined accurately by_______________?
A. Newton
B. Michelson
C. Huygen
D. Young - Light on passing through a Polaroid is ___________________?
A. plane polarized
B. un-polarized
C. circularly polarized
D. elliptically polarized
