MYTUTOR SUBJECT ANSWERS

221 views

What is the De Broglie wavelength of an electron given it has a kinetic energy of 1 eV? You are given the mass of an electron is 9.11x10^-31 kg and Planck's constant is 6.63x10^-34

The De Broglie wavelength equation is as follows:

λ=h/p

We know the value of Planck's constant h and so to calculate the wavelength all we need is the momentum, which is equal to mv.

The kinetic energy is given as 1 eV. Remember 1 eV is equal to 1.6 x 10-19 Joules. Using the equation for kinetic energy and the given mass of the electron we can determine the velocity of the electron as follows:

K.E = 0.5*m*v2

Which can be rearranged to be in terms of velocity v:

v = (2*K.E*m)0.5

By substituting in 1.6 x 10-19 for K.E and 9.11 x 10-31 for m we get v = 5.93 x 105 ms-1 (remember to keep the full non-rounded value in your calculator!)

Then using the initial equation for the wavelength and remembering p = mv, we can substitute in our values for h, m and v as follows:

λ = 6.33 x 10-34 / (9.11 x 10-31 x 5.93 x 105)  

λ = 1.17 x 10-9 m

David  M. A Level Physics tutor, GCSE Physics tutor, A Level Maths tu...

9 months ago

Answered by David , an A Level Physics tutor with MyTutor

Still stuck? Get one-to-one help from a personally interviewed subject specialist

48 SUBJECT SPECIALISTS

£20 /hr

Tom C.

Degree: Engineering Science (Masters) - Oxford, Jesus College University

Subjects offered: Physics, Maths+ 3 more

Physics
Maths
Further Mathematics
.PAT.
-Oxbridge Preparation-

“About me I’m Tom, I’m a third year Engineer at Oxford University. I’m very patient and friendly and I’ve always had love for how things are put together, this has gone onto the science behind it. In our lessons I want to show you what...”

£22 /hr

Jordan H.

Degree: MPhys Physics with Professional Experience (Masters) - Exeter University

Subjects offered: Physics, Maths+ 2 more

Physics
Maths
Chemistry
Biology

“Hi, I'm Jordan, a first year Physics undergraduate hoping to help both A-level and GCSE students in Maths and Physics.”

£20 /hr

Peter W.

Degree: Aerospace Engineering (Masters) - Queen's, Belfast University

Subjects offered: Physics, Maths+ 1 more

Physics
Maths
Further Mathematics

“Second year Aerospace Engineering student at Queen's University Belfast. Happy to offer help in Maths, Further Maths and Physics at GCSE and A-Level, which I have great experience in both learning and tutoring.”

About the author

David M.

Currently unavailable: until 25/11/2016

Degree: Physics (Masters) - Warwick University

Subjects offered: Physics, Maths+ 2 more

Physics
Maths
Chemistry
.PAT.

“Background I am a second year physics student studying at the University of Warwick. I am passionate about helping people learn and allowing them to attain thehigh grades which they deserve. My love of science and mathematics will com...”

MyTutor guarantee

You may also like...

Posts by David

How do I show two lines are skew?

If the highest frequency a song is 10 kHz and it is encoded at 16 bits per sample what is the minimum number of bytes needed to encode the 3 minute song?

What is the De Broglie wavelength of an electron given it has a kinetic energy of 1 eV? You are given the mass of an electron is 9.11x10^-31 kg and Planck's constant is 6.63x10^-34

Other A Level Physics questions

Explain Rutherford's atomic model experiment

A stationary observer Bob, observes Alice take 5 seconds to travel from point A to B at 0.95c. How much time does Alice measure the journey from A to B to take?

The speed of water moving through a turbine is 2.5 m/s. Show that the mass of water passing through an area of 500 metres squared in one second is about 1 x 10^6 kg (density of sea water = 1030 kg/m^3)

What is simple harmonic motion?

View A Level Physics tutors

Cookies:

We use cookies to improve our service. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok