Wave Optics — Physics STD 12 Science — Question

Which of the following phenomena establishes the particle nature of light ?

Radioactive nuclei that are injected into a patient collect at certain sites within its body, undergoing radioactive decay and emitting electromagnetic radiation. These radiations can then be recorded by a detector. This procedure provides an important diagnostic tool called(a) Gamma camera(b) CAT scan(c) Radiotracer technique(d) Gamma ray spectroscopy

The force between two charges 0.06 m apart is 5 N. If each charge is moved towards the other by 0.01 m, then the force between them will become(a) 7.20 N(b) 11.25 N(c) 22.50 N(d) 45.00 N

Second law of Kirchhoff depends on the principle of conservation of:

The dimensions of dipole moment are:

The resistor of resistance 'R' is connected to 25 V supply and heat produced in it is 25 J/sec. The value of R is(a) 225 Ω (b) 1 Ω (c) 25 Ω    (d) 50 Ω

A person is suffering from the defect astigmatism. Its main reason is(a) Distance of the eye lens from retina is increased(b) Distance of the eye lens from retina is decreased(c) The cornea is not spherical(d) Power of accommodation of the eye is decreased

Which of the following is a natural magnet?

The mass of a neutral carbon atom in ground state is:

1. Exact 12u
2. Less than 12u
3. More than 12u
4. Depends on the form of carbon such as graphite or charcoal.

The focal length of a convex lens is 10 cm and its refractive index is 1.5.  If the radius of curvature of one surface is 7.5 cm, the radius of curvature of the second surface will be(a) 7.5 cm (b) 15.0 cm(c) 75 cm (d) 5.0 cm