Intensity = number of photons, frequency = energy of each photonतीव्रता = फोटॉनों की संख्या, आवृत्ति = प्रत्येक फोटॉन की ऊर्जाIntensity = number of photons, frequency = energy of each photon

NCERT Sec 11.6–11.7 · Class 12 Physics · Chapter 11 · interactive diagram

Parts and what they mean

• Dim violet light (मंद बैंगनी प्रकाश) — Few photons per second, each of energy hc/λ = 3.10 eV (> 2.75 eV), so a few electrons come out — instantly.
• Bright violet light (तीव्र बैंगनी प्रकाश) — More photons per second, same energy each: more electrons (bigger current) but the same Kmax = 3.10 − 2.75 = 0.35 eV.
• Bright red light (तीव्र लाल प्रकाश) — Each photon has only 1.91 eV < 2.75 eV. However bright, no electron is emitted (ν < ν0).
• Sodium plate (सोडियम प्लेट) — Work function 2.75 eV (a commonly quoted value); threshold wavelength about 451 nm.
• No emission (कोई उत्सर्जन नहीं) — Below the threshold frequency, intensity does not help.

Original diagram drawn by Simple Learning Hub, based on NCERT Sec 11.6–11.7. Report a mistake