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### IITJEE Test series 2 (Modern Physics)

(A) Multiple choice questions with one answer
1. The ionizing power of the radiations are in the increasing order of
(a) γ,β ,α
(b) α , β,γ
(c) α , γ,β
(d) β, γ,α

2.A photon of energy 5.0 eV imparts all it's energy to an electron that leaves a metal surface with 1.5 eV of kinetic energy.The work function α of metal would be
(a) 6.5 eV
(b) 3.5 eV
(c) 3.9 eV
(d) 1.5 eV

3. A thermal neutron of mass 1.67× 10-27 Kg is travelling at a speed of 2500 m/s. de Brogli wavelength of thermal neutron is
(a) 1.4 × 10-10m
(b) 12 × 10-10m
(c) 1.6 × 10-10m
(d) 1.0 × 10-10m

4. Uncertainity in the position of a particle is equal to twice its de Brogli wavelength. Uncertainity in its velocity would be
(a) Δvx≥(1/4π)vx
(b) Δvx≥(1/π)vx
(c) Δvx≥(1/2π)vx
(d) Δvx≥(1/8π)vx

5. The shortest wavelength of X-Rays emitted from an X-Ray tube depends upon
(a) atomic number of target material
(b) current in the tube
(c) voltage applied to the tube
(d) nature of gas in the tube

6. The largest wavelength present in the Balmer series of hydrogen atom is
(a) 656 nm
(b) 500 nm
(c) 600 nm
(d) 756 nm

(B) Matrix match type
Match the list P with the list Q to name the series for quantum jump of electrons in hydrogen atom

list P
(a) n=2 to n=3
(b) n=3 to n=4
(c) n=4 to n=5
(d) n=5 to n=6

list Q
1. Balmer
2. lyman
3. Paschen
4. Brackett
5. Pfund

(A) Multiple choice questions with one answer
1. a
2. b
3. c
4. d
5. c
6. d

(B) Matrix match type
a-2
b-1
c-3
d-4