Current Electricity — Physics STD 12 Science — Question

 Pick out the correct increasing order of energy of electromagnetic waves from the following:

Diffusion current in a p-n junction is greater than the drift current in magnitude:

In a certain double slit experimental arrangement interference fringes of width 1.0 mm each are observed when light of wavelength 5000 Å is used. Keeping the set up unaltered, if the source is replaced by another source of wavelength 6000 Å, the fringe width will be(a) 0.5 mm(b) 1.0 mm(c) 1.2 mm(d) 1.5 mm

The idea of the quantum nature of light has emerged in an attempt to explain(a) Interference(b) Diffraction(c) Radiation spectrum of a black body(d) Polarisation

Two charged particles traverse identical helical paths in a completely opposite sense in a uniform magnetic field.

Resistance of one carbon filament and one tungsten lamp are measured individually when the lamp are lit and compared with their respective resistances when cold. Which one of the following statements will be true(a) Resistance of the carbon filament lamp will increase but that of the tungsten will diminish when hot(b) Resistance of the tungsten filament lamp will increase but that of carbon will diminish when hot(c) Resistances of both the lamps will increase when hot(d) Resistances of both the lamps will decrease when hot

Hydrogen atom emits blue light when it changes from n = 4 energy level to the n = 2 level. Which colour of light would the atom emit when it changes from the n = 5 level to the n = 2 level(a) Red(b) Yellow(c) Green   (d) Violet

What is ozone hole(a) Hole in the ozone layer(b) Formation of ozone layer(c) Thinning of ozone layer in troposphere(d) Reduction in ozone thickness in stratosphere

The activity of a radioactive sample is 1.6 curie and its half-life is 2.5 days. Its activity after 10 days will be(a) 0.8 curie(b) 0.4 curie(c) 0.1 curie(d) 0.16 curie