Alternating Current — Physics STD 12 Science — Question

Define the term 'wattless current'.

When is a Wheatstone’s bridge most sensitive?

Which of the statements is true for p-type semiconductos.

1. Electrons are majority carriers and trivalent atoms are the dopants.
2. Electrons are minority carriers and pentavalent atoms are the dopants.
3. Holes are minority carriers and pentavalent atoms are the dopants.
4. Holes are majority carriers and trivalent atoms are the dopants.

The length of the string of a simple pendulum is measured with a metre scale to be 90.0cm. The radius of the bob plus the length of the hook is calculated to be 2.13cm using measurements with a slide callipers. What is the effective length of the pendulum? (The effective length is defined as the distance between the point of suspension and the centre of the bob.)

Draw the pattern of electric field lines, when a point charge –Q is kept near an uncharged conducting plate.

A capacitor has capacitance C. Is this information sufficient to know what maximum charge the capacitor can contain? If yes, what is this charges? If no, what other information is needed?

How does de Broglie wavelength depend on the momentum of a particle?

Define the term 'electrical conductivity' of a metallic wire. Write its S.I unit.

Which part of electromagnetic spectrum form sun is absorbed by the ozone layer?

Is it always true that the molecules of a dense liquid are heavier than the molecules of a lighter liquid?