Ray Optics and Optical Instruments — Physics STD 12 Science — Question

Attenuation is measured in :

A parallel plate condenser is connected with the terminals of a battery. The distance between the plates is 6mm. If a glass plate (dielectric constant K  = 9) of 4.5 mm  is introduced between them, then the capacity will become(a) 2 times(b) The same(c) 3 times(d) 4 times

A wave is propagating in a medium of electric dielectric constant 2 and relative magnetic permeability 50. The wave impedance of such a medium is(a) 5 W    (b) 376.6 W(c) 1883 W(d) 3776 W

A charged conducting sphere does not produce an electric field:

Making a light wave vibrate in only one plane is known as:

In cyclotron the gyro radius is:

The sensitivity of a potentiometer can be increased by:

• increasing the series resistance in the primary circuit.
• decreasing the length of the potentiometer wire.
• using a thin and high resistivity wire as a potentiometer wire.
• increasing the length of the wire.

Two atoms of the same element are found to have different number of neutrons in their nuclei. These two atoms are:

Pick the correct options:

Which of the following in a hydrogen atom is independent of the principal quantum number n? (The symbols have their usual meanings).