# Physics Class-12 Chapter-12 Atoms Most VVI Objective Questions

Q.1. Which series comes in visible region of hydrogen spectrum ?

(A) Lyman series

(B) Blamer series

(C) Paschen series

(D) Brackett series

Ans:- (B)

Q.2. The minimum angular momentum of electron in hydrogen atom will be

(A) h/π Js

(B) nh/2π Js

(C) hπ Js

(D) 2πh Js

Ans:- (B)

Q.3. The number of photons of frequency 10¹⁴ Hz in radiation of 6.62 joule will be

(A) 10¹⁰

(B) 10¹⁵

(C) 10²⁰

(D) 10²⁵

Ans:- (C)

Q.4. Who had studied the visible region of hydrogen spectrum for the first time ?

(A) Balmer

(B) Lyman

(C) Brackett

(D) Pfund

Ans:- (A)

Q.5. The SI unit of Rydberg constant

(A) m⁻¹

(B) m

(C) s⁻¹

(D) s

Ans:- (A)

Q.6. The electrons in Bohr atom move in circular orbit due to

(A) nuclear force

(B) gravitational force

(C) coulomb force

(D) none of these

Ans:- (C)

Q.7. Thomson method determines

(A) momentum of electron

(B) charge of electron

(C) mass of electron

(D) the ratio of charge to mass

Ans:- (D)

Q.8. Dimensional formula of Rydberg’s constant is

(A) [M⁰L⁻¹T⁰]

(B) [MLT⁻¹]

(C) [M⁰LT⁰]

(D) [M⁰L⁰T⁰]

Ans:- (A)

Q.9. Which of the following atoms has the lowest ionization potential ?

(A) ₇N¹⁴

(B) ₅₅Cs¹³³

(C) ₁₈Ar⁴⁰

(D) ₈O¹⁶

Ans:- (B)

Q.10.