https://teddyrookbook.com/physics/physics-2/Recent content in Physics 2: Fluids, Heat, Electricity, Light and Atoms on Teddy Rook Bookhttps://teddyrookbook.com/img/share.jpghttps://teddyrookbook.com/img/share.jpgHugoenhttps://teddyrookbook.com/physics/physics-2/pressure-depth/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/pressure-depth/In a still fluid P = P₀ + ρgh, and gauge pressure leaves out the air pressure above. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/pascals-principle/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/pascals-principle/A pressure change spreads through a confined fluid, so a small force on a small piston lifts a heavy load. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/buoyancy/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/buoyancy/The fluid pushes up with the weight of the fluid displaced, F_b = ρ_fluid·V·g, and a floating object displaces its own weight. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/continuity/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/continuity/For a liquid filling a pipe, the flow rate Av is the same everywhere: A₁v₁ = A₂v₂. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/bernoulli/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/bernoulli/Along a streamline P + ½ρv² + ρgh stays the same, so faster-moving fluid has lower pressure. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/ideal-gas-law/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/ideal-gas-law/PV = nRT = Nk_BT, with the temperature in kelvins. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/kinetic-theory/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/kinetic-theory/Each gas molecule has average kinetic energy (3/2)k_BT, so a monatomic gas holds internal energy U = (3/2)nRT. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/latent-heat/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/latent-heat/Melting or boiling a mass m takes Q = mL; add the warming stages to find the total heat. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/conduction-rate/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/conduction-rate/Heat flows through a slab at the rate P = kAΔT/L, so thinner and wider walls pass more. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/thermal-radiation/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/thermal-radiation/Every object radiates P = eσAT⁴, and hotter objects glow at shorter peak wavelengths: λ_max·T = 2.898 × 10⁻³ m·K. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/pv-work/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/pv-work/W = −PΔV is the work done on the gas, and its size is the area under the path on a P–V diagram. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/first-law/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/first-law/ΔU = Q + W: the internal energy changes by the heat added plus the work done on the gas. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/thermo-processes/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/thermo-processes/Each process holds one thing fixed, which decides how Q, W and ΔU split. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/thermo-cycles/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/thermo-cycles/Around a closed cycle ΔU = 0, and the area enclosed is the net work. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/heat-engines/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/heat-engines/An engine turns part of the heat Q_H into work and gives off the rest as Q_C, with efficiency e = W/Q_H. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/carnot-limit/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/carnot-limit/No engine running between T_H and T_C can beat e = 1 − T_C/T_H, with temperatures in kelvins. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/refrigerators/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/refrigerators/Work can move heat from cold to hot, and a heat pump delivers more heat than the work it uses. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/entropy/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/entropy/Heat flows from hot to cold on its own; ΔS = Q/T, and the total entropy of an isolated system never decreases. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/charge-conservation/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/charge-conservation/Charge comes in whole multiples of e and is conserved, and objects charge by friction, contact or induction. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/coulombs-law/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/coulombs-law/F = k|q₁q₂|/r²: double the distance and the force drops to a quarter. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/coulomb-superposition/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/coulomb-superposition/The net force on a charge is the vector sum of the forces from each of the other charges. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/electric-field/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/electric-field/E = F/q is the force on each coulomb; a point charge makes E = k|q|/r², pointing away from a positive charge. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/field-superposition/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/field-superposition/Add the field vectors from each charge; field lines show the direction, and their spacing shows the strength. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/uniform-field/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/uniform-field/Between parallel plates E is uniform, so a charge feels a constant force qE and moves like a projectile. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/electric-potential-energy/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/electric-potential-energy/Two charges store U = kq₁q₂/r, positive when they repel and negative when they attract. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/electric-potential/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/electric-potential/Potential is energy per charge, V = kq/r near a point charge, and a charge crossing ΔV gains or loses qΔV of kinetic energy. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/equipotentials/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/equipotentials/The field points from high to low potential, at right angles to equipotentials, with E = ΔV/d between plates. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/capacitors/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/capacitors/C = Q/V, and for parallel plates C = κε₀A/d. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/capacitor-energy/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/capacitor-energy/A charged capacitor stores U = ½QV = ½CV². Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/current/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/current/I = ΔQ/Δt, and conventional current points the way positive charge would flow. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/resistivity/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/resistivity/R = ρL/A, so longer and thinner wires resist more. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/resistor-power/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/resistor-power/P = IV = I²R = V²/R are three forms of one idea. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/series-resistors/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/series-resistors/One current passes through every resistor, the voltages add, and R_eq = R₁ + R₂ + ⋯. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/parallel-resistors/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/parallel-resistors/Each branch has the same voltage, 1/R_eq = 1/R₁ + 1/R₂ + ⋯, and adding a branch lowers R_eq. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/combination-circuits/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/combination-circuits/Reduce a circuit step by step, then work back out to find each current and voltage. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/kirchhoff-junction/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/kirchhoff-junction/The current flowing into a junction equals the current flowing out, because charge is conserved. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/kirchhoff-loop/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/kirchhoff-loop/The voltage changes around any closed loop add to zero, because energy is conserved. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/internal-resistance/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/internal-resistance/A real battery's terminal voltage is ε − Ir, so it sags as the current grows. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/capacitor-combinations/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/capacitor-combinations/Parallel capacitances add, and series capacitances combine by reciprocals, the opposite of resistors. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/rc-circuits/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/rc-circuits/A capacitor charges through a resistor with time constant τ = RC, and once full it blocks steady current. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/magnetic-fields/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/magnetic-fields/Magnets and moving charges make magnetic fields, measured in teslas, whose lines form closed loops. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/force-on-moving-charge/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/force-on-moving-charge/F = qvB sin θ, at right angles to both v and B, by the right-hand rule. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/charged-particle-circles/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/charged-particle-circles/The magnetic force is centripetal, so r = mv/(|q|B), and it never changes the speed. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/force-on-wire/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/force-on-wire/A wire carrying current I across a field B feels F = ILB sin θ. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/field-of-wire/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/field-of-wire/A long wire makes B = μ₀I/(2πr) in circles around it, a solenoid makes a nearly uniform B = μ₀nI inside, and parallel currents attract. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/magnetic-flux/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/magnetic-flux/Φ = BA cos θ counts the field passing through a loop, with θ measured from the loop's normal. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/faradays-law/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/faradays-law/A changing magnetic flux makes an emf: ε = −N ΔΦ/Δt. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/lenzs-law/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/lenzs-law/The induced current makes a field that opposes the change in flux. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/motional-emf/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/motional-emf/A rod sliding along rails at speed v makes ε = BLv, and the force on the induced current slows the rod. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/reflection/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/reflection/The angle of reflection equals the angle of incidence, and a plane mirror's image is as far behind it as the object is in front. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/index-of-refraction/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/index-of-refraction/n = c/v: light slows in glass and water, and its wavelength shrinks while its frequency stays the same. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/snells-law/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/snells-law/n₁ sin θ₁ = n₂ sin θ₂, with angles measured from the normal. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/total-internal-reflection/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/total-internal-reflection/Going from higher to lower n, light beyond the critical angle, sin θc = n₂/n₁, reflects completely. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/mirror-ray-diagrams/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/mirror-ray-diagrams/Three principal rays locate the image formed by a concave or convex mirror. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/mirror-equation/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/mirror-equation/1/f = 1/dₒ + 1/dᵢ and m = −dᵢ/dₒ, with signs that mark real and virtual images. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/lens-ray-diagrams/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/lens-ray-diagrams/Converging and diverging lenses bend parallel rays toward or away from a focal point. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/thin-lens-equation/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/thin-lens-equation/The mirror equation works for lenses too, and real images form on the far side of the lens. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/wave-speed-medium/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/wave-speed-medium/The medium sets the speed, v = √(tension/μ) on a string, and the source sets the frequency. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/wave-graphs/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/wave-graphs/A y–x graph shows the whole wave at one instant; a y–t graph follows one point over time. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/wave-boundaries/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/wave-boundaries/A pulse reflects upside down from a fixed end and right side up from a free end, and partly passes into a new medium. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/em-waves/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/em-waves/Light is a wave of linked electric and magnetic fields moving through empty space at c = fλ. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/polarization/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/polarization/Only transverse waves can be polarized; a polarizer passes half of unpolarized light and I₀cos²θ of polarized light. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/superposition/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/superposition/Overlapping waves add point by point: crest on crest builds up, crest on trough cancels. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/standing-waves-strings/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/standing-waves-strings/A string fixed at both ends resonates at fₙ = nv/(2L). Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/standing-waves-pipes/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/standing-waves-pipes/Open pipes resonate at fₙ = nv/(2L); pipes closed at one end only at odd multiples of v/(4L). Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/sound-intensity/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/sound-intensity/Intensity falls off as 1/r², and β = 10 log(I/I₀), so adding 10 dB means 10 times the intensity. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/doppler/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/doppler/A source moving toward you sounds higher and one moving away sounds lower: f′ = f·v/(v ∓ vₛ). Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/single-slit/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/single-slit/Waves spread out past an opening, and a single slit makes dark fringes where a sin θ = mλ. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/double-slit/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/double-slit/Bright fringes appear where the path difference is a whole number of wavelengths: d sin θ = mλ. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/diffraction-grating/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/diffraction-grating/Many evenly spaced slits make sharp bright lines at d sin θ = mλ, where d is 1 divided by the number of lines per meter. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/thin-films/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/thin-films/Light reflecting from the top and bottom of a thin film interferes, with a half-wave flip at each reflection off a higher index. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/photons/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/photons/Light comes in photons of energy E = hf = hc/λ, and 1 eV = 1.602 × 10⁻¹⁹ J. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/photoelectric-effect/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/photoelectric-effect/An electron escapes a metal only if a single photon brings more than the work function: Kₘₐₓ = hf − φ. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/bohr-model/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/bohr-model/Electrons in atoms have only certain energies, and a jump between levels absorbs or emits a photon whose energy is the difference between the two levels. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/spectra/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/spectra/A hot thin gas emits bright lines, and the same gas in front of a hotter source absorbs those same lines. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/matter-waves/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/matter-waves/Particles have a wavelength λ = h/p, so electrons diffract like light. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/compton-scattering/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/compton-scattering/A photon carries momentum p = h/λ, so an X-ray that bounces off an electron comes away with a longer wavelength. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladderhttps://teddyrookbook.com/physics/physics-2/mass-energy/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/physics-2/mass-energy/E = mc²: a nucleus has less mass than its separate protons and neutrons, and the missing mass is its binding energy. Physics 2: Fluids, Heat, Electricity, Light and Atoms · Physics Ladder