PHYSICS FINAL EXAM

Metamers are what

Different spectra but same perceived color

Why do metamers occur

Cones respond to ranges of wavelengths

What is a spectral color

A single wavelength from the rainbow

What is a perceived color

A color created by cone responses, not a single wavelength

Increasing aperture does what to f-number

Decreases f-number

Increasing aperture does what to depth of field

Makes shallow/small DOF

What does shallow DOF look like

Blurry background, small focus region

Decreasing aperture does what to f-number

Increases f-number

Decreasing aperture does what to depth of field

Makes large DOF

What does large DOF look like

Sharp everywhere

What does index of refraction depend on

Frequency

Which color has higher index of refraction

Blue

Why does blue bend more than red

Higher frequency increases n

Constructive interference means what

Wavelengths add to make bright

Destructive interference means what

Wavelengths cancel to make dark

Absorption filters do what

Absorb unwanted wavelengths and transmit one

Dichroic filters do what

Reflect unwanted wavelengths and transmit one

What is dichromacy

Missing one cone type

Which cone is missing in protanopia

Red cone

Which cone is missing in deuteranopia

Green cone

Which cone is missing in tritanopia

Blue cone

What is anomalous trichromacy

All three cones present but one is shifted

Which cones can be shifted in anomalous trichromacy

Only one cone shifts (L or M or S)

1 mm equals what in meters

1 × 10^-3 m

4.5 mm equals what in meters

4.5 × 10^-3 m

Single slit formula is what

y = (λD) / b

Double slit formula is what

y = (λD) / d

What is a hard reflection

Light goes from low n to high n and flips phase 180 degrees

What is a soft reflection

Light goes from high n to low n with no phase change

Dichromacy & Anomalous are remembered by

(Missing one & Shifted one)

PRDGTB

People. Remember. Dogs. Go. To. Bed.

What direction do electric fields point from positive charges?

Outward

What direction do electric fields point toward negative charges?

Inward

What do electric field lines show?

Direction a positive test charge would move

What did early vacuum tubes use to push electrons?

High voltage through low‑pressure gas

What particle was later shown to move through vacuum tubes?

Electrons

What is the photoelectric effect?

Light ejecting electrons from a metal surface

What determines whether electrons are ejected in the photoelectric effect?

Light frequency above a threshold

What does increasing brightness above threshold change?

Number of electrons ejected, not their energy

Can low‑frequency light eject electrons even if very bright?

No

What does the classical model incorrectly say light’s energy depends on?

Amplitude

What classical prediction fails in the photoelectric effect?

Brighter low‑frequency light should eject electrons

What key observation does the classical model fail to explain?

Threshold frequency

What does the photon model say light consists of?

Photons

What determines a photon’s energy?

Frequency

What does brighter light mean in the photon model?

More photons, not stronger photons

What is the formula for photon energy?

E = hν

What is the alternate photon energy formula?

E = hc/λ

What did Rutherford’s gold foil experiment test?

The plum pudding model

What did most alpha particles do in the gold foil experiment?

Passed through

What did this show about atoms?

Mostly empty space

What did deflected alpha particles show?

Existence of a small, dense, positive nucleus

If an atom were the size of a campus, how big would the nucleus be?

About the size of a grape

What did the flawed planetary model imagine electrons doing?

Orbiting like planets

What did the planetary model incorrectly predict?

Electrons should lose energy and spiral into the nucleus

What could the planetary model NOT explain?

Discrete energy levels or threshold frequency

What does the Bohr model say about electron energy?

It is quantized

What does higher n mean in the Bohr model?

Higher energy and larger orbit radius

How does energy spacing change as n increases?

Spacing decreases

What happens when an electron drops to a lower level?

Emits a photon

What determines photon wavelength in transitions?

λ = hc / (E₂ − E₁)

What is wave‑particle duality?

Light and electrons behave as both waves and particles

How large are electron wavelengths?

Around atomic scale

What forms standing waves around the nucleus?

Electrons

What determines allowed electron orbits?

Whole numbers of wavelengths fitting in orbit

What happens when a photon with matching energy hits an atom?

Electron absorbs it and jumps up

What happens when an electron falls to a lower orbit?

Emits a photon

Why does each atom have a unique spectrum?

Unique energy levels

What does the quantum model say electrons form?

A probabilistic electron cloud

What shapes do orbitals have?

s, p, d, f

What causes electrons to jump in a vacuum tube?

Photoelectric effect

What increases brightness?

Number of photons (amplitude)

What did Rutherford’s experiment show about atoms?

Mostly empty space

Where are protons and neutrons located?

In the nucleus

Where are electrons located?

Outside the nucleus

Which electrons have the highest energy?

Those farthest from the nucleus

What must photon energy match for absorption/emission?

Difference between energy levels

Why do different atoms have different spectral fingerprints?

Different energy level spacings

What does atomic number define?

Element identity and electron binding strength

Are energy levels continuous or discrete?

Discrete

What does larger atomic number mean for energy gaps?

Larger gaps

Why do atoms have multiple emission lines?

Multiple possible transitions

What does spectroscopy reveal?

Composition, temperature, density, motion

What does the Webb telescope use?

Infrared spectroscopy

What is the Lyman series?

Transitions to n = 1 (UV)

What is the Balmer series?

Transitions to n = 2 (visible)

What is the Paschen series?

Transitions to n = 3 (infrared)

What is H‑alpha?

Transition E₃ → E₂ (656 nm)

What happens in photoionization?

Electron ejected, atom becomes positive ion

Does atomic number change in ionization?

No

What produces a continuous spectrum?

Blackbody radiation

What produces an emission spectrum?

Excited gas emitting photons

What produces an absorption spectrum?

Gas absorbing specific wavelengths

What happens when white light passes through gas?

Specific wavelengths absorbed and re‑emitted randomly

What causes Fraunhofer lines in the Sun?

Cooler atmosphere absorbing wavelengths

How was helium discovered?

Unknown solar absorption lines

What is blueshift?

Wavelengths shorten as source moves toward observer

What is redshift?

Wavelengths lengthen as source moves away

Given λ₀ = 656.3 nm and λobs = 657.1 nm, what is Δλ?

0.8 nm

Whats hyperopia

When you focus after the f