1-Dont try to cram or spend more time here just read it fast and cover syllabus then practice MCQ's cheptor of same topic to check your progress. . |
2-Wrong options are also given but dont concentrate there, Right answer is in bold format. |
Q21 ⇒ Assertion (A): When an electron is revolving in its orbit and magnetic field is also present, the angular frequency of electron will be affected by the magnetic field. Reason (R): In the case of electron revolving in its orbit in the presence of magnetic field, the orbital magnetic dipole moment is not affected by the presence of magnetic field. A is true but R is false [other wrong options] [Discuss in forum] Both A and R are true and R is correct explanation of A Both A and R are true but R is not correct explanation of A A is false but R is true |
Q22 ⇒ In a specimen of ferromagnetic material, as the flux density is increased from zero to 2.5 T, µr will first increase then decrease [other wrong options] [Discuss in forum] increase decrease first decrease then increase |
Q23 ⇒ Assertion (A): Helium, Argon and Neon are gaseous at room temperature. Reason (R): The atoms in Helium, Argon and Neon are chemically extremely inactive. Both A and R are true and R is correct explanation of A [other wrong options] [Discuss in forum] Both A and R are true but R is not correct explanation of A A is true but R is false A is false but R is true |
Q24 ⇒ The relaxation time of electrons in a metal is of the order of 10-14 secs [other wrong options] [Discuss in forum] 10-6 secs 10-10 secs 10-20 secs |
Q25 ⇒ Assertion (A): Orbital magnetic moment of an electron in an atom is of the order of 1 Bohr magneton. Reason (R): 1 Bohr magneton = 9.27 x 10-24 A/m2. Both A and R are true but R is not correct explanation of A [other wrong options] [Discuss in forum] Both A and R are true and R is correct explanation of A A is true but R is false A is false but R is true |
Q26 ⇒ The transition of electron from energy level W1 to W2 is associated with emission or absorption of electro magnetic radiation of frequency f such that hf = |W1 - W2| [other wrong options] [Discuss in forum] |W1 - W2|f = h hf = 0.5|W1 - W2| (hf)2 = |W1 - W2| |
Q27 ⇒ Assertion (A): Diamond and carborudum are both very hard materials. Reason (R): Valence band can be extremely strong. Both A and R are true and R is correct explanation of A [other wrong options] [Discuss in forum] Both A and R are true but R is not correct explanation of A A is true but R is false A is false but R is true |
Q28 ⇒ When a ferromagnetic substance is magnetised there are small changes in dimensions. This phenomenon is called magnetostriction [other wrong options] [Discuss in forum] hysteresis diamagnetism dipolar relaxation |
Q29 ⇒ An electrolytic capacitor can be used for dc only [other wrong options] [Discuss in forum] ac only both ac and dc high frequency ac |
Q30 ⇒ Electric dipole moment is usually expressed in debye units. Here, 1 debye unit equals 3.33 x 10-30 C-m [other wrong options] [Discuss in forum] 3.33 x 10-30 C-m2 3.30 x 10-10 C-m 3.33 x 10-10 C-m2 |
Q31 ⇒ In its lowest state, the electron is bound to the field of proton by an energy equal to 13.6 eV [other wrong options] [Discuss in forum] 100.5 eV 51.2 eV 0.2 eV |
Q32 ⇒ A copper atom is neutral. Its core has a net charge of 1 [other wrong options] [Discuss in forum] 0 -1 2 |
Q33 ⇒ The units for electric dipole moment are colomb-metre [other wrong options] [Discuss in forum] coulombs coulomb/metre coulomb/m2 |
Q34 ⇒ Magnetic hysteresis phenomenon is explained by motion of domain walls and domain rotation [other wrong options] [Discuss in forum] motion of domain walls domain rotation none of the above |
Q35 ⇒ For an insulating material, dielectric strength and dielectric losses should be high and low [other wrong options] [Discuss in forum] high and high low and high low and low |
Q36 ⇒ The relative permeability of a ferromagnetic material is 1000 or more [other wrong options] [Discuss in forum] 1 less than 1 about 10 |
Q37 ⇒ When Schrodinger equation is applied to the motion of electron in the field of protons, the physically acceptable solutions for the wave function exist for quantum number which are 3 [other wrong options] [Discuss in forum] 2 4 5 |
Q38 ⇒ Assertion (A): Atomic number of sodium is 11. Reason (R): Sodium has a body centred cubic lattice. Both A and R are true but R is not correct explanation of A [other wrong options] [Discuss in forum] Both A and R are true and R is correct explanation of A A is true but R is false A is false but R is true |
Q39 ⇒ If B, H and M denote flux density, field intensity and magnetisation, B = μ0 (H + M). TRUE [other wrong options] [Discuss in forum] FALSE |
Q40 ⇒ Assertion (A): Silicon is less sensitive to changes in temperature than germanium. Reason (R): Cut in voltage in silicon is less than that in germanium. A is true but R is false [other wrong options] [Discuss in forum] Both A and R are true and R is correct explanation of A Both A and R are true but R is not correct explanation of A A is false but R is true |
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