Home
Class 12
PHYSICS
A proton (m(p) = 1.673 xx 10^(-27) kg) a...

A proton `(m_(p) = 1.673 xx 10^(-27) kg)` and an electron `(m = 9.109 xx 10^(-31) kg)` are confined such that the position x of each is known within `1.50 xx 10^(-10) m`. What is the ratio of the minimum uncertainty in the x component of the velocity of the electron to that of the proton, `Deltav_(e)// Deltav_(p)`?

Text Solution

AI Generated Solution

The correct Answer is:
To find the ratio of the minimum uncertainty in the x-component of the velocity of the electron to that of the proton, we can use the Heisenberg Uncertainty Principle. The principle states that: \[ \Delta x \Delta p \geq \frac{h}{4\pi} \] where: - \(\Delta x\) is the uncertainty in position, - \(\Delta p\) is the uncertainty in momentum, - \(h\) is Planck's constant (\(h \approx 6.626 \times 10^{-34} \, \text{Js}\)). The momentum \(p\) of a particle is given by: \[ p = mv \] where \(m\) is the mass and \(v\) is the velocity. Therefore, the uncertainty in momentum can be expressed as: \[ \Delta p = m \Delta v \] Substituting this into the uncertainty principle gives: \[ \Delta x \cdot (m \Delta v) \geq \frac{h}{4\pi} \] From this, we can solve for \(\Delta v\): \[ \Delta v \geq \frac{h}{4\pi m \Delta x} \] Now, we will calculate \(\Delta v\) for both the electron and the proton. 1. **Calculate \(\Delta v_e\) for the electron:** - Mass of the electron \(m_e = 9.109 \times 10^{-31} \, \text{kg}\) - Uncertainty in position \(\Delta x = 1.50 \times 10^{-10} \, \text{m}\) \[ \Delta v_e \geq \frac{h}{4\pi m_e \Delta x} \] Substituting the values: \[ \Delta v_e \geq \frac{6.626 \times 10^{-34}}{4\pi (9.109 \times 10^{-31})(1.50 \times 10^{-10})} \] Calculating this gives: \[ \Delta v_e \geq \frac{6.626 \times 10^{-34}}{4\pi \times 9.109 \times 10^{-31} \times 1.50 \times 10^{-10}} \] Evaluating the denominator: \[ \approx 4\pi \times 9.109 \times 10^{-31} \times 1.50 \times 10^{-10} \approx 8.577 \times 10^{-40} \] So, \[ \Delta v_e \geq \frac{6.626 \times 10^{-34}}{8.577 \times 10^{-40}} \approx 7.73 \times 10^{5} \, \text{m/s} \] 2. **Calculate \(\Delta v_p\) for the proton:** - Mass of the proton \(m_p = 1.673 \times 10^{-27} \, \text{kg}\) \[ \Delta v_p \geq \frac{h}{4\pi m_p \Delta x} \] Substituting the values: \[ \Delta v_p \geq \frac{6.626 \times 10^{-34}}{4\pi (1.673 \times 10^{-27})(1.50 \times 10^{-10})} \] Evaluating the denominator: \[ \approx 4\pi \times 1.673 \times 10^{-27} \times 1.50 \times 10^{-10} \approx 3.152 \times 10^{-36} \] So, \[ \Delta v_p \geq \frac{6.626 \times 10^{-34}}{3.152 \times 10^{-36}} \approx 2.10 \times 10^{2} \, \text{m/s} \] 3. **Calculate the ratio \(\frac{\Delta v_e}{\Delta v_p}\):** \[ \frac{\Delta v_e}{\Delta v_p} = \frac{7.73 \times 10^{5}}{2.10 \times 10^{2}} \approx 3,683.33 \] Thus, the ratio of the minimum uncertainty in the x-component of the velocity of the electron to that of the proton is approximately: \[ \frac{\Delta v_e}{\Delta v_p} \approx 3,683 \]
Promotional Banner

Topper's Solved these Questions

  • PHOTONS AND MATTER WAVES

    RESNICK AND HALLIDAY|Exercise PRACTICE QUESTIONS(Matrix - Match)|5 Videos
  • OSCILLATIONS

    RESNICK AND HALLIDAY|Exercise Practice Questions|57 Videos
  • RELATIVITY

    RESNICK AND HALLIDAY|Exercise PRACTICE QUESTIONS (Integer Type)|5 Videos

Similar Questions

Explore conceptually related problems

For an electron whose x-positional uncertainty is 1.0 xx 10^(-10) m . The uncertainty in the x - component of the velocity in ms^(-1) will be the order of :

If the electron is to be located within 5 xx 10^(-5) what will be the uncertainty in the velocity ?

For an electron whose positional uncertainly is 1.0xx10^(-10)m , the uncertainty in the component of the velocity in ms^(-1) will be

The position of both an electron and a helium atom is known within 1.0 nm and the momentum of the electron is known within 50 xx 10^-26 kg ms^-1 . The minimum uncertainty in the measurement of the momentum of the helium atom is.

A proton of mass 1.66 xx 10^(-27) kg is moving with kinetic energy 5 xx 10^(-17) J .What is the wavelength of proton ?

A electron of mass 9xx10^(-31) kg is revolving in a stable circular orbit or radius 1.8xx10^(-12) m in a hydrogen atom. If the electrostatic froce of attraction between the proton and electron is 8xx10^(-8) N, the velosity of the electron is

The mass of an electron is 9.11 x 10^-31 kg, that of a proton is 1.67 x 10^-27 kg. Find the ratio F_e// F_g of the electric force and the gravitational force exerted by the proton on the electron.-