Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEET 2020
Exam
NEET
Year
2020
Subject
Physics
Chapter
Electromagnetic Waves

NEET 2020 · Physics · Electromagnetic Waves

Light with an average flux of 20W cm ^ - 2 falls on a...

Light with an average flux of 20Wcm−220W{cm}^{- 2} falls on a non-reflecting surface at normal incidence having surface area 20cm220{cm}^{2}. The energy received by the surface during time span of 1min1min is:

Options

  1. A12×103J12 \times {10}^{3}J
  2. B24×103J24 \times {10}^{3}J
  3. C48×103J48 \times {10}^{3}J
  4. D10×103J10 \times {10}^{3}J

Correct answer

B. 24×103J24 \times {10}^{3}J

Step-by-step solution

We know that, I=EAtI = \dfrac{E}{At}

E=IAtE = IAt

⇒E=2010−4×20×10−4×60⇒ E = \dfrac{20}{{10}^{- 4}} \times 20 \times {10}^{- 4} \times 60

⇒E=24×103J⇒ E = 24 \times {10}^{3}J

Practice Electromagnetic Waves on Quantrex Academy →

More from Electromagnetic Waves

A parallel-plate capacitor of 50\ contains a dielectric slab of constant ( k ) with the… MHT CET Medical 2026An electromagnetic wave travelling in a lossless dielectric medium having a dielectric… NEET 2026Match List I with List II : List I (Electromagnetic wave) List II (Production) A.… NEET 2026The following table presents the part of the electromagnetic spectrum and their… NEET 2026A parallel plate capacitor made of circular plates is being charged such that the surface… NEET 2025The electric field in a plane electromagnetic wave is given by E_z=60 (5 x+1.5 × 10^9 t)… NEET 2025A parallel plate capacitor is charged by connecting it to a battery through a resistor.… NEET 2024The electromagnetic radiation which has the smallest wavelength are NEET 2024 Full Electromagnetic Waves list All NEET PYQs