Optics Answers

A 2-meter-long pendulum with a 1 kg bob is pulled back from its equilibrium position 25 degrees. 

a. What is its potential energy at that point? 

b. What is its kinetic energy as it passes through the equilibrium position? 

c. What is the pendulum’s maximum velocity?

Determine the stopping distances for an automobile going a constant initial speed of 93km/h and human reaction time of 0.30 s, for an acceleration a=−3.3m/s2.

Calculate the minimum deviation produced by a 60° glass prism if the refractive index of the glass is

    1.50. What is the angle of incidence at which minimum deviation occurs?

 Calculate the minimum deviation produced by a 60° glass prism if the refractive index of the glass is

    1.50. What is the angle of incidence at which minimum deviation occurs?

 A ray of light is incident in water on a plane water-glass boundary. The angle of incidence is 30°.

   Calculate the angle of deviation.

  A ray of light is incident in air at an angle of 40° to the normal to one face of a 60° glass prism.

   Calculate the angle through which the ray has been deviated by the time it emerges from the prism.

   A narrow parallel pencil of monochromatic light is incident on a plane boundary between air and

glass. Describe the phenomena which occur as the angle of incidence of the light is progressively

increased from 0° to 90°, (a.) in the air, (b.) in the glass.                    

A parallel beam of light of wavelength 5.5 × 10^-7m in air is incident on the slits in Young's double slit experiment. A thin film of transparent plastic of refractive index 1.48 and thickness

5.2µm is placed over one of the slits.

(i.) Determine the increase in the optical path of the light passing through the thin film.

(ii.) Determine the number of fringes by which the central fringe is displaced.

(iii.) Explain how the fringe spacing would change if:

     • The slit separations were increased.

     • The slit-screen distances were increased.

(a ) Differentiate between interference and diffraction of light.

(a ) What is meant by a coherent light source?

(b) Describe how you would determine the wavelength of monochromatic light using Young's

double slit. Your account should include a diagram, observations, precautions, and how you use the

observations to reach conclusions.