Electromagnetic Waves — Physics STD 12 Science — Question

Magnetic induction is a(a) Scalar quantity(b) Vector quantity(c) Both (a) and (b)(d) None of the above

Choose the correct statement(a) When we heat a semiconductor its resistance increases (b) When we heat a semiconductor its resistance decreases (c) When we cool a semiconductor to 0 K then it becomes super conductor(d) Resistance of a semiconductor is independent of temperature

The binding energy per nucleon is maximum in the case of

Additivity of the electric charges means that the total charge of a system is the _____ of all individual charges in the system.

The x-component of the resultant of several vectors:

1. Is equal to the sum of the x-components of the vectors.
2. May be smaller than the sum of the magnitudes of the vectors.
3. May be greater than the sum of the magnitudes of the vectors.
4. May be equal to the sum of the magnitudes of the vectors.

Assertion   :  Coloured spectrum is seen when we look through a muslin cloth.
Reason       : It is due to the diffraction of white light on passing through fine slits.(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.