Electromagnetic Induction — Physics STD 12 Science — Question

Assertion  : Bohr had to postulate that the electrons in stationary orbits around the nucleus do not radiate.
Reason      : According to classical physics all moving electrons radiate. (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.

Assertion  :   If different gases are filled turn by turn at the same pressure in the discharge tube the discharge in them takes place at the same potential.
Reason      : The discharge depends only on the pressure of discharge tube and not on the ionisation potential of gas.(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.

For nuclei with A > 100:

In a cassette player, material used for coating magnetic tapes is:

Two point charges + Q and + q are separated by a certain distance. If + Q > + q then in between the charges the electric field is zero at a point.

A parallel plate capacitor of plate area A has a charge Q. The force on each plate of the capacitor is

Assertion  : Density of all the nuclei is same.
Reason      : Radius of nucleus is directly proportional to the cube root of mass number.(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.