Question 1

The wavelength of a 45-kg teenager moving at 5 m/s on a skateboard is about

Accepted Answer

A) 5 × 10−37 m. 
B) 3 × 10−36 m. 
C) 7 × 10−34 m. 
D) 0.1 m. 
E) 5 m.

Question 2

An electron is sitting on a pinpoint having a diameter of 2.5 μm.What is the minimum uncertainty in the speed of the electron?

Accepted Answer

The answer of An electron is sitting on a pinpoint...

Question 3

A quantum particle

Accepted Answer

A) can be localized in space. 
B) can be represented by an infinitely long wave having a single frequency. 
C) can be represented by a wave packet. 
D) travels at the phase speed of the infinitely long wave having the highest frequency. 
E) has the highest probability of being present in those regions of space where its component waves interfere destructively.

Question 4

What is the maximum kinetic energy (in eV)of a photoelectron when a surface,whose work function is 5.0 eV,is illuminated by photons whose wavelength is 400 nm?

Accepted Answer

A) 3.1 
B) −1.9 
C) 1.9 
D) 0 
E) 1.2

Question 5

If a rubidium surface is irradiated with blue light of wavelength 450.0 nm,what is the kinetic energy of the electrons emitted? (The work function for rubidium is φ = 2.09 eV. )

Accepted Answer

The answer of If a rubidium surface is irradiated with...

Question 6

A photon whose energy is 8.00 × 10−15 J is scattered off an electron at a 90° angle.What is the wavelength of the scattered wave?

Accepted Answer

A) 2.73 × 10−11 m 
B) 2.25 × 10−11 m 
C) 2.50 × 10−11 m 
D) 2.40 × 10−12 m 
E) 2.48 × 10−11 m

Question 7

Assume the Heisenberg uncertainty principle can take the form ΔEΔt ≥ h/4B.How accurate can the position of an electron be made if its speed is 5 × 106 m/s and if the uncertainty in its energy is 10 eV?

Accepted Answer

A) 7.7 × 10−18 m 
B) 1.3 × 10−23 m 
C) 6.2 × 10−15 m 
D) 1.6 × 10−10 m 
E) 1.2 × 10−9 m

Question 8

A solid state pulsed laser has an energy of 400 mJ per pulse.If its wavelength is 1.06 × 10−6 m,how many photons are in each pulse?

Accepted Answer

A) 2 × 1025 
B) 2 × 1021 
C) 3 × 1018 
D) 6 × 1038 
E) 2 × 1018

Exam 40: Introduction to Quantum Physics

The wavelength of a 45-kg teenager moving at 5 m/s on a skateboard is about

An electron is sitting on a pinpoint having a diameter of 2.5 μm.What is the minimum uncertainty in the speed of the electron?

A quantum particle

What is the maximum kinetic energy (in eV) of a photoelectron when a surface,whose work function is 5.0 eV,is illuminated by photons whose wavelength is 400 nm?

If a rubidium surface is irradiated with blue light of wavelength 450.0 nm,what is the kinetic energy of the electrons emitted? (The work function for rubidium is φ = 2.09 eV. )

A photon whose energy is 8.00 × 10−¹⁵ J is scattered off an electron at a 90° angle.What is the wavelength of the scattered wave?

Assume the Heisenberg uncertainty principle can take the form ΔEΔt ≥ h/4B.How accurate can the position of an electron be made if its speed is 5 × 10⁶ m/s and if the uncertainty in its energy is 10 eV?

A solid state pulsed laser has an energy of 400 mJ per pulse.If its wavelength is 1.06 × 10−⁶ m,how many photons are in each pulse?