๐ Unit 5: Modern Physics โ Mid-Unit Diagnostic
Assessment FOR Learning
๐ Not Graded โ Teacher Feedback Only
Purpose: Diagnose readiness for the modern-physics unit. Prerequisites: kinetic energy and momentum (Unit 2), wave-particle duality (Unit 4), photon energy \(E=hf\), exponents and logarithms.
Section A โ Prerequisites (Knowledge & Understanding)
Q1 โ Kinetic energy & momentum [3]
An electron (\(m=9.11\times10^{-31}\,\text{kg}\)) moves at \(2.0\times10^{6}\,\text{m/s}\). Find (a) its KE in joules, (b) its momentum.
Q2 โ Photon energy (Unit 4 review) [2]
A photon of frequency \(6.0\times10^{14}\,\text{Hz}\) has what energy in joules and in eV? (\(h = 6.63\times10^{-34}\,\text{Jยทs}\))
Q3 โ Exponents/logs warm-up [2]
Solve for \(t\): \(0.25 = (1/2)^{t/10}\). Show the use of logarithms.
Section B โ Bridge to New Concepts (Thinking)
Q4 โ Frames of reference [4]
In Newtonian mechanics, two observers in different inertial frames disagree on velocity but agree on time and length. State which of these does Einstein's special relativity say also disagree, and predict whether the disagreement is significant for a car at \(100\,\text{km/h}\) โ justify quantitatively.
Q5 โ Wave or particle? [3]
Identify whether the wave model, particle model, or both are needed to explain each: (a) interference fringes, (b) photoelectric effect, (c) electron diffraction, (d) refraction.
Section C โ Reflection (Communication)
Q6 โ Conceptual challenge [2]
Which idea in modern physics do you find most counter-intuitive (e.g., time dilation, mass-energy equivalence, wave-particle duality)? What helps your understanding?