Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

Which of the following shows that the earth behaves as a magnet?

The coordination number of Cu  is (a) 1(b) 6 (c) 8  (d) 12

Assertion  :   Faraday’s laws are consequences of conservation of energy.
Reason      : In a purely resistive ac circuit, the current lags behind the e.m.f. in phase. (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 the assertion and reason both are false.

According to Coulomb’s law, the coulomb force measured between two point charges is inversely proportional to:

The specific resistance of a rod of copper as compared to that of thin wire of copper is:

In case of a semiconductor, which of the following statement is wrong(a) Doping increases conductivity(b) Temperature coefficient of resistance is negative(c) Resisitivity is in between that of a conductor and insulator(d) At absolute zero temperature, it behaves like a conductor