Electrons moving in a beam have the same de Broglie wavelength as protons in a separate beam moving at a speed of 2.8 × 10^4 m/s . What is the speed of the electrons?

de Broglie wavelength formula:
λ = h/mv,
whereλ = wavelength,h = Planck's Constant = 6.626 x 10-34 Js,m = mass of object,v = object's velocity,
Mass of proton mp = 1.6726219 × 10-27 kg,Velocity of proton vp = 2.8 × 104 ms-1 ,Mass of electron me = 9.11 × 10-31 kg,
de Broglie wavelength of proton λp= h/mpvp = (6.626x10-34)/[(1.6726219 × 10-27)(2.8 × 104)] = 1.4170 x 10-11 m,de Broglie wavelength of electron λe= h/meve = λp= 1.4170 x 10-11 m,
Rearranging for ve, we get,
ve= h/λeme, ve = (6.626x10-34)/[(1.4170 x 10-11)(9.11 × 10-31)],ve = 5.1328 x 107 ms-1,ve = 5.1 x 107 ms-1 (correct to 2 significant figures)

Answered by Haider A. Physics tutor

8911 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

Explain the process of annihilation?


what is the scape velocity?


A block of mass m is released from rest on a surface inclined at 30⁰ to the horizontal with a coefficient of friction of 0.3. How long does it take for the block to slide 1 m?


Why is an object moving in a circle at a constant speed said to be accelerating?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences