JEE Advanced | 2013Electromagnetic WavesHard

Question

A pulse of light of duration 100 ns is absorbed completely by a small object initially at rest. Power of the pulse is 30 mW and the speed of light is 3 × 108 ms-1. The final momentum of the object is :-

Options

A.0.3 × 10-17 kg ms-1 
B.1.0 × 10-17 kg ms-1 
C.3.0 × 10-17 kg ms-1 
D.9.0 × 10-17 kg ms-1 

Solution


Energy incident = P (time)
              = 30 mW (100 ns)
              = 3 × 10-9
So momentum 10-17 kg m/sec.

Create a free account to view solution

View Solution Free
Topic: Electromagnetic Waves·Practice all Electromagnetic Waves questions

More Electromagnetic Waves Questions

The electric field of an electromagnetic wave in free space is given by = 10 cos(107 t + kx)V/m, where t and x are in se...If a source of power 4 kW produces 1020 photons/second, the radiation belong to a part of the spectrum called...Which of the following are not electromagnetic waves?...A plane electromagnetic wave is moving in free space with velocity c $= 3 \times 10^{8}\text{ }m/s$ and its electric fie...Energy from the Sun falls on the Earth surface at the rate of 1400 W/m2, which is known as solar constant. The respectiv...