Wave Motion and Waves on a String — Physics STD 12 Science — Question

Source of Sun's energy is (a) Burning of hydrogen(b) Fission reactions involving hydrogen(c) Fusion reactions involving hydrogen(d) Some other source

Who discovered spin quantum number(a) Unlenbeck and Goudsmit(b) Nell’s Bohr(c) Zeeman(d) Sommerfield

The refractive index of a certain glass is 1.5 for light whose wavelength in vacuum is 6000 Å. The wavelength of this light when it passes through glass is(a) 4000 Å (b) 6000 Å (c) 9000 Å (d) 15000 Å 

Which of the following rays are not electromagnetic waves(a) g-rays (b) b-rays(c) Heat rays(d) X-rays

Audio signal cannot be transmitted because (a) The signal has more noise(b) The signal cannot be amplified for distance communication (c) The transmitting antenna length is very small to design(d) The transmitting antenna length is very large and impracticable

Assertion  :  Thin films such as soap bubble or a thin layer of  oil on water show beautiful colours when illuminated by white light.
 Reason     : It happens due to the interference of light reflected from the upper surface of the thin film. (a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.

The equation E = pc is valid:

To increase the angular magnification of a simple microscope, one should increase: