Chapter 38, Problem 35A

(a)

To determine

Whether the electron or proton has the more momentum.

Explanation of Solution

Introduction:

The momentum depends on the mass and speed of the object. If the speed of two objects is same then the momentum of the massive object will be more.

The electrons and protons move with same speed in an atom but the mass of the proton is more than the mass of electron. The momentum of the proton is more than the momentum of the electron because the mass of proton is more than the mass of electron.

Conclusion:

The proton has more momentum than electron.

(b)

To determine

Whether the electron or proton has the longer wavelength.

Explanation of Solution

Introduction:

The wavelength of the object depends on the momentum of the object. If the momentum of the object increases then the wavelength of the object decreases. The heavier the mass of the object more the momentum of the object becomes and the less is the wavelength of the object become.

The proton is heavier than the electron, so the proton has more momentum. The wavelength of the object varies inversely with the momentum of the object. The momentum of the proton is greater than the momentum of electron, so the wavelength of the proton is less than the wavelength of the electron.

Conclusion:

The wavelength of the electron is longer than the wavelength of the proton.