A parallel beam of monochromatic light of frequency v is incident on a surface. Intensity of the beam is I and area of the surface is A. Find the forc

Monjur Alahi

A parallel beam of monochromatic light of frequency v is incident on a surface. Intensity of the beam is I and area of the surface is A. Find the force exerted by the light beam on the surface for following cases–
(i) the surface is perfectly absorbing and the light beam is incident normally on it.
(ii) the surface is perfectly reflecting and the light beam is incident normally.
(iii) the surface is perfectly absorbing and the light beam is incident at an angle of incidence `theta`.
(iv) the surface is perfectly reflecting and the light beam is incident at an angle of incidence `theta`.


0 like 0 dislike
1 views
Share with your friends

1 Answers

Salim Ahmed Kawsar

Call

Correct Answer - (i) `(IA)/(c)` , (ii) `(2IA)/(c)`
(iii) `(Iacostheta)/(c)` , (iv) `(2IAcos^(2)theta)/(c)`

0 like 0 dislike
1 views
Talk Doctor Online in Bissoy App
A beam of monochromatic light is incident at `i= 50^(@)` on one face of an equilateral prism, the angle of emergence is `40^(@)`, then the angle of mi

Correct Answer - B `I = 50^(@)` , equilateral prism `A = 60^(@) , e= 40^(@)` Total angle of deviation `delta =i+e - A = 50 + 40 - 60, delta=...

2 Answers 1 views
When light of wavelength `lambda` is incident on a metal surface, stopping potential is found to be x. When light of wavelength n`lambda` is incident

Let `lambda_(0)` is the threshold wavelength. The work function is `phi = (hc)/(lambda_(0))` Now, by photoelectric equation `ex = (hc)/(lambda) - (hc)/(lambda_(0))` ……(i) `(ex)/(n+1) = (hc)/(nlambda) - (hc)/(lambda_(0))`……..(ii) From (i)...

2 Answers 3 views
A vertical beam of light of cross sectional radius `(R)/(2)` is incident symmetrically on the curved surface of a glass hemisphere of refractive index

Correct Answer - `0.34 R`

2 Answers 1 views
An electron beam having a speed of `10^(7)ms^(-1)` passes through the two plates of a parallel plate capacitor. The electric intensity between the pla

Correct Answer - 0.003516 rad

2 Answers 1 views
Photoelectric work function for a surface is 2.4 eV. Light of wavelength `6.8 xx 10^(-7)`m shines on the surface. Find the frequency of incident light

Correct Answer - `v =4.41 xx 10^(14)Hz,v_(0)=5.82 xx 10^(14) Hz`, no photoelectric emission occurs as `v lt v_(0)`

2 Answers 1 views
When light of wavelength 400nm is incident on the cathode of photocell, the stopping potential recorded is 6V. If the wavelength of the incident light

Correct Answer - 4.97 V

2 Answers 7 views
White light is incident normally on a plane parallel thin film of µ=1.5. Find the minimum thickness of the film for which light of `lamda`=4000 Å is a

Correct Answer - `1.33xx10^(-7)`m

2 Answers 2 views
A parallel beam of sodium light of wavelength 5896 Å is incident at angle `30^(@)`. Find the minimum thickness of the glass plate for which the transm

Correct Answer - `1.135xx10^(-7)`m

2 Answers 1 views
A parralel beam of monochromatic light of wavelength 5000 Å is incident normally in a narrow slit of width 0.25 mm. The diffraction pattern is observe

Correct Answer - `6xx10^(-3)rad`

2 Answers 1 views
A beam of light travelling in water falls on a glass plate immersed in water. When the incident angle is `51^(@)`, the reflected beam of light is foun

Correct Answer - 1.647

2 Answers 1 views
X