**NEET Physics Chapter Wise Mock Test – Matter Waves**

**Question 1:
**Nuclear radii may be measured by scattering high energy electrons from nuclei. What is the de-broglie wavelength for 200 MeV electrons

(a) 8.28 fm

(b) 7.98 fm

(c) 6.45 fm

(d) 6.20 fm

**Question 2:
**A particle is dropped from a height H. The de-Broglie wavelength of the particle as a function of height is proportional to

(a) H

(b) H

^{1/2}

(c)H

^{0}

(d) H

^{-1/2}

**Question 3:
**Monochromatic light of frequency 6.0x 10

^{14}Hz is produced by a laser. The power emitted is 2 x 10

^{-3}W. The number of photons emitted, on the average by the source per second is

(a) 5 x 10

^{15}

(b) 5 x 10

^{16}

(c) 5×10

^{17}

(d) 5 x 10

^{14}

**Question 4:
**If an electron and a proton have the same de-Broglie wavelength, then the kinetic energy of the electron is

(a) zero

(b) less than that of proton

(c) more than that of a proton

(d) equal to that of proton

**Question 5:
**The de-Broglie wavelength of a proton. (charge = 1.6×10

^{-19}C, m =1.6 x10

^{-27}kg) accelerated through a potential difference of 1 kV is

(a) 600Å

(b) 0.9x 10

^{-12}m

(c) 7Å

(d) 0.9 nm

**Question 6:
**If α, β and γ rays carry same momentum which has the longest wavelength?

(a) α rays

(b) β rays

(c) γ rays

(d) All have same wavelength

**Question 7:
**What is de-Broglie wavelength of a dust particle of mass 1 x 10

^{-9}kg drifting with a speed of 2.2 m/s?

(a) 1.1 x 10

^{-32}m

(b) 3.01 x 10

^{-25}m

(c) 1.1 x 10

^{-3}m

(d) 3.01 x 10

^{-2}m

**Question 8:
**

**Question 9:
**The de-Broglie wavelength of 1 MeV proton is

(a) 6.63 x 10

^{-34}m

(b) 3.33 x 10

^{-30}m

(c) 2.32 x 10

^{-20}m

(d) 2.86 x 10

^{-14}m

**Question 10:
**The de-Broglie wavelength of a bus moving with speed v is λ. Some passengers left the bus at a stoppage. Now, when the bus moves with twice its initial speed, its kinetic energy is found to be twice its initial value. The de-Broglie wavelength will now

(a) λ

(b) 2λ

(c) λ/2

(d) λ/4

**Question 11:
**Energy of neutrofi in eV whose de-Broglie wavelength is 1Å

(a) 1.674 x 10

^{-27}eV

(b) 8.13 x 10

^{-2}eV

(c) 6.62 x 10

^{-22}eV

(d) 3.23x 10

^{-2}eV

**Question 12:
**

**Question 13:
**An α-particle and a deuteron are moving with the same kinetic energy. What will be the ratio of their de-Broglie wavelengths?

(a) 1/√2

(b) 2

(c) 1

(d) √2

**Question 14:
**What will be the number of photons emitted per second by a 10W sodium vapour lamp assuming that 90% of. the consumed energy is converted into light? Wavelength of sodium light is 590 nm, h=6.63×10

^{-34}J-s.

(a) 0.267×10

^{18}

(b) 0.267×10

^{19}

(c) 0.267×10

^{20}

(d) 0.267×10

^{17}

**Question 15:
**If the energy of photons corresponding to the wavelength of 6000Å is 3.2 x 10

^{-19}J, the photon energy for a wavelength of 4000Å will be

(a) 1.11 x 10

^{-19}J

(b) 2.22x 10

^{-19}J

(c) 4.40 x 10

^{-19}J

(d) 4.80 x 10

^{-19}J

**Question 16:
**In the Davisson Germer experiment, if the incident beam consists of electrons, then the diffracted beam consists of

(a) protons

(b) neutrons

(c) α-particles

(d) electrons

**Question 17:
**X-rays of wavelength λ

_{0}= 0.200 nm are scattered from a block of material. The scattered X-rays are observed at an angle of 45° to the incident beam. Calculate their wavelength.

(a) 0.300700 nm

(b) 0.100710 nm

(c) 0.200710 nm

(d) 0.400710 nm

**Question 18:
**

**Question 19:
**The wavelength of a photon needed to remove a proton from a nucleus which is bound to the nucleus with 1 MeV energy is nearly

(a) 1.2nm

(b) 1.2×10

^{-3}nm

(c) 1.2 x10

^{-6}nm

(d) 1.2×10

^{1}nm

**Question 20:
**Monochromatic light of wavelength 3000Å is incident on a surface area 4 cm

^{2}. If intensity of light is 150 mWm

^{-2}, then rate at which photons strike the target is .

(a) 3 x 10

^{10}s

^{-1}

(b) 9x 10

^{13}s

^{-1}

(c) 7 x 10

^{15}s

^{-1}

(d) 6x 10

^{19}s

^{-1}

**Question 21:
**According to the Moseley’s law, the frequency of characteristic X-rays is related to the atom in number of target element as

(a) Z

(b) Z

^{2}

(c) Z

^{-1}

(d) Z

^{-2}

**Question 22:
**In Thomson’s experiment for the measurement of elm of an electron is 10

^{5}Vm

^{-1}and the magnetic field is 10

^{-2}T. The beam was originally accelerated through a potential difference of 285 V. The value of specific charge of electron will be

(a) 1.67 x 10

^{11}Ckg

^{-1}

(b) 1.47 x 10

^{11}Ckg

^{-1}

(c) 1.74x 10

^{11}Ckg

^{-1}

(d) None of these

**Question 23:
**Energy from the sun is received on the earth at the rate of 2 cal per cm

^{2}per min. If average wavelength of solar light be taken at 5500Å, then how many photons are received on the earth per cm

^{2}per min?

(a) 1.5 x 10

^{13}

(b) 2.9 x10

^{2}

(c) 2.3 x10

^{19}

(d) 1.5 x 10

^{3}

**Question 24:
**An electron is moving with an initial velocity v = v

_{0}i and is in a magnetic field B = B

_{0}j . Then, it’s de-Broglie wavelength

(a) remains constant

(b) increases with time

(c) decreases with time

(d) increases and decreases periodically

**Question 25:
**

**Question 26:
**The momentum of a photon of energy 1 MeV in kgms

^{-1}will be

(a) 0.33×10

^{6}

(b) 7x 10

^{-24}

(c) 10

^{-22}

(d) 5 x 10

^{-22}

**Question 27:
**The X-ray tube is operated at 50 kV. The minimum wavelength produced, is

(a) 0.5Å

(b) 0.75Å

(c) 0.25Å

(d) 1.0Å

**Question 28:
**A radiation energy E falls normally on a perfectly reflecting surface. The momentum transferred to the surface is (C = Velocity of light)

(a) E/C

(b) 2E/C

(c) 2E/C

^{2}

(d) E/C

^{2}

**Question 29:
**A certain metallic surface is illuminated with monochromatic light of wavelength λ. The stopping potential for photoelectric current for this light is 3V

_{0}. If the same surface is illuminated with light of wavelength 2λ, the stopping potential is V

_{0}. The threshold wavelength for this surface for photoelectric effect is

(a) 6λ

(b) 4λ

(c) λ/4

(d) λ/6

**Question 30:
**A parallel beam of fast moving electrons is incident normally on a narrow slit. A fluorescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, then which of the following statements is correct?

(a) Diffraction pattern is not observed on the screen in the case of electrons

(b) The angular width of the central maximum of the diffraction pattern will increase

(c) The angular width of the central maximum will be decrease

(d) The angular width of the central maximum will be unaffected

**Question 31:
Assertion(A): **X-ray are used for studying the structure of crystals.

**The difference between the atoms of crystal is of the order of wavelength of X-rays.**

Reason(R):

Reason(R):

(a) If both assertion and reason are true and reason is the correct explanation of assertion

(b) If both assertion and reason are true but the reason is not the correct explanation of assertion

(c) If assertion is true but reason is false

(d) If both assertion and reason are false

**Question 32:
**If the end A of a wire is irradiated with α-rays and the other end B is irradiated with β-rays, then

(a) a current will flow from A to B

(b) there will be no current in the wire

(c) a current will flow from B to A

(d) a current will flow from each end of the mid-point of the wire

**Question 33:
**What should be the velocity of an electron, so that its momentum becomes equal to that of a photon of wavelength 52000Å?

(a) 700 m/s

(b) 1000 m/s

(c) 1400 m/s

(d) 2800 m/s

**Question 34:
**What kV potential is to be applied on X-ray tube, so that minimum wavelength of emitted X-ray may be 1Å (h = 6.6 x 10

^{-34}J-s)

(a) 12.42 kV

(b) 12.84 kV

(c) 11.98 kV

(d) 10.78 kV

**Question 35:
**Solar radiation is

(a) transverse electromagnetic wave

(b) longitudinal electromagnetic wave

(c) stationary wave

(d) None of the above

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