The mass of an electron is 9 .1 × 10 - 31 kg . If its K.E. is 3 .0 × 10 - 25 J , calculate its wavelength.

Given: The mass of an electron = 9 .1 × 10 - 31 kg Kinetic energy (K.E) of the electron = 3 .0 × 10 - 25 J Since K.E. = 1 2 mv 2 ∴ Velocity v = 2 K . E m = 2 × 3 .0 × 10 - 25 J 9 . 1 × 10 - 31 kg = 0 . 6593 × 10 6 v = 811 . 99 ms - 1 From de Broglie’s equation, wavelength ( λ ) = h mv h = 6 .62 × 10 - 34 Js Substituting all values in the expression of λ : λ = 6 .62 × 10 - 34 Js 9 .1 × 10 - 31 kg 811 . 99 m s - 1 = 8 .959 × 10 - 7 m ≅ 8 .95 × 10 - 7 m

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

A body of mass

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v

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v_{0}

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

A mass

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S . H . M .

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A_{1}

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M

passes through its mean position, then a smaller mass

m

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A_{2}

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The number of spherical nodes in

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

Similar to electron diffraction, neutron diffraction microscope is also used for the determination of the structure of molecules. If the wavelength used here is

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The number of spherical nodes in 3p orbitals are

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

Which of the following choice is the correct form of the Schrodinger wave equation?

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

Calculate the wavelength of an electron moving with a velocity of

2 .05 \times 10^{7} m s^{- 1}

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The measurement of the electron position is associated with an uncertainty in momentum, which is equal to

1 \times 10^{- 18} g cm s^{- 1}

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9 \times 10^{- 28} g

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

Frequency of matter wave is equal to

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The probability of finding the electron in the orbital is

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

If the position of the electron is measured within an accuracy of

\underline{+} 0 .002 nm

, calculate the uncertainty in the momentum of the electron. Suppose the momentum of the electron is

h / 4 π_{m} \times 0 .05 nm

, is there any problem in defining this value.

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The nodes present in

3 p

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

A particle moving with a velocity

10^{6}

m / s

will have de Broglie wavelength nearly [Given,

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

Dual behavior of matter proposed by de Broglie led to the discovery of electron microscope often used for the highly magnified images of biological molecules and other type of material. If the velocity of the electron in this microscope is

1 .6 \times 10^{6} {ms}^{- 1},

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

Heisenberg's uncertainty principle has no significance for a moving

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

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53 Å

and then decreases to zero.

Reason [R]: Bohr's radius for the first orbit is

53 Å

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The de-Broglie wavelength of a tennis ball of mass

60 g

moving with a velocity of

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is approximately (Planck's constant,

h = 6 .63 \times 10^{- 34} Js

)

MEDIUM

Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The mass of an electron is

9 .1 \times 10^{- 31} kg

. If its K.E. is

3 .0 \times 10^{- 25} J

, calculate its wavelength.

MEDIUM

Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

The number of local maxima in the radial distribution curve of

5 d

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Physics>Oscillations and Waves>Waves>Principle of Superposition of Waves

What will be the number of waves formed by a Bohr electron in one complete revolution in its second orbit?

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Important Questions on Waves

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