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The number of photons of wavelength of 540 nm emitted per second by an electric bulb of power 100 W is (given h=6×10⁻³⁴ J-s)
Options
(a) 100
(b) 1000
(c) 3×10²⁰
(d) 3×10¹⁸
Correct Answer:
3×10²⁰
Explanation:
Power = nhc / ( × t)
⇒ 100 = [n × (6 × 10⁻³⁴) × (3 × 10⁸)] / (540 × 10⁹ × 1)
⇒ n × 18 × 10⁻²⁶ / 540 × 10⁻⁹ = 100
⇒ n = 100 × 540 × 10⁻⁹ / 18 × 10⁻²⁶ = 3 x 10²⁰
Related Questions: - A potentiometer wire of length 10 m and resistance 10 Ω per metre is connected in series
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Topics: Dual Nature of Matter and Radiation
(150)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- A potentiometer wire of length 10 m and resistance 10 Ω per metre is connected in series
- An electron in potentiometer experiences a force 2.4×10⁻¹⁹N. The length of potentiometer
- The temperature coefficient of the resistance of a wire is 0.00125 per ⁰C.
- A light emitting diode(LED) has a voltage drop of 2 volt across it
- Two discs of moment of inertia l₁ and I₂ and angular speeds
Topics: Dual Nature of Matter and Radiation (150)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
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