Einstein’s Photoelectric Equation Challenge
25 NEET-standard questions on why the wave picture fails, Einstein’s photon idea, K_max = hν − φ₀, threshold frequency, stopping potential and the V₀–ν graph. Answer each one. If you get it wrong, Vidya Ma’am explains it with an animated movie you can control, a slider to play with, and a step-by-step solution. Then try again.
NCERT Physics XII Part II · Ch. 11 · pp. 280–282Keys: A–D or 1–4 to answer
🧠 Formula memory tricks (open before you start)
Photon energyE = hνE(eV) ≈ 1243 ÷ λ(nm)
Einstein’s equationKmax = hν − φ₀eV₀ = hν − φ₀
Thresholdν₀ = φ₀/hbelow ν₀: no emission, however intense
Intensity vs frequencyIntensity = number of photons: changes the current. Frequency changes Kmax and V₀.
V₀–ν graphV₀ = (h/e)ν − φ₀/eslope h/e · ν-intercept φ₀/h · V₀-intercept −φ₀/e
TimingPhotoemission starts in about 10⁻⁹ s or less, even for very dim light.wave picture: hours
Constantsh = 6.63×10⁻³⁴ J s · e = 1.6×10⁻¹⁹ Ch/e = 4.14×10⁻¹⁵ V s
right first tryfixed after explanationstill to fix
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