Magnetism And Matter — Physics STD 12 Science — Question

Light waves can be polarised because they:

According to Kirchhoff's law, at any junction in an electric circuit:

A 100 watt bulb working on 200 volt and a 200 watt bulb working on 100 volt have(a) Resistances in the ratio of 4 : 1(b) Maximum current ratings in the ratio of 1 : 4 (c) Resistances in the ratio of 2 : 1(d) Maximum current ratings in the ratio of 1 : 2

If a 2 kW boiler is used everyday for 1 hour, then electrical energy consumed by boiler in thirty days is(a) 15 unit(b) 60 unit(c) 120 unit(d) 240 unit

Consider a wire carrying a steady current, I placed in a uniform magnetic field B perpendicular to its length. Consider the charges inside the wire. It is known that magnetic forces do no work. This implies that:

A body is positively charged, it implies that:

Assertion   :   Separation of isotope is possible because of the difference in electron numbers of isotope.
Reason       : Isotope of an element can be separated by using a mass spectrometer. (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 assertion is false but reason is true.

Which one of them is a radioisotope?

. A surface that has the same electrostatic potential at every point on it is known as _____________.