Question

6.) A light ray traveling in air, n = 1.0, is incident (angle of incidence = 45 ^o ) upon a boundary with another medium, n = 1.2, therefore, the light ray transmitted into the second medium is refracted as follows;

   a.) transmission angle is less than 45 ^o

   b.) transmission angle is equal to 45 ^o

   c.) transmission angle is greater than 45 ^o

   d.) transmission angle is unknowable

Answer__________

7.) A light beam passes from air (n_air = 1.00) into a transparent material (n = 1.414). The angle of incidence is 45 ^o . Use Snell’s law to calculate the angle of refraction.

   a.) 30 ^o

   b.) 20 ^o

   c.) 50 ^o

   d.) 70 ^o

Answer __________

8.) Consider a convex lens with a 45.00 centimeter focal length. Calculate the object distance if the image distance is 135.00 centimeter.

   a.) 25.00 centimeters

   b.) 57.50 centimeters

   c.) 33.75 centimeters

   d.) 67.50 centimeters

Answer__________

9.) An object is placed at the radius of curvature for a convex lens. The real image formed has a magnification of - 1.0 (the minus sign indicates inverted image). If the object distance is decreased slightly, then

           

   a.) the image becomes virtual and the magnification becomes positive.

   b.) the image instantly disappears.

   c.) the image remains real and the magnification becomes more negative.

  

Answer__________

10.) Determine the magnification for an astronomical refracting telescope with a focal length of the objective lens equal to 0.200 m and a focal length for the eyepiece equal to 0.010 m.

   a.) 50

   b.) 40

   c.) 20

   d.) 10

Answer

11.) In a reflecting telescope, the light from the astronomical object is collected and focused by the most important component which is

   a.) mirror

   b.) lens

   c.) collimator

   d.) camera holder

Answer__________

12.) Telescopes in low earth orbit have the advantage of

   a.) no atmospheric disturbances

   b.) visibility at all wavelengths

   c.) no scattering of city lights in the images

   d.) all of the above

Answer __________

Answer 1

6) using snell's law ,

n₁sin(theta)₁ = n₂sin(theta)₂

theta₂ = 36.1 which is less than 45 degree. Option A is correct.

7) Using same formula as above,

n₁sin(theta)₁ = n₂sin(theta)₂  where n₁ = 1, n₂ = 1.414 ,

I found theta₂ = 30

8) Use lens equation

1/f = 1/u - 1/v

1/u = 1/f - 1/v

1/u = 1/45 - 1/135

u = 67.5 cm  

9) m = - d_image / d_object

If we increase the d_object , m will increase. and minus sign will cancel out

10) For telecope, m = f_objective / f_eyepiece

m = 0.2 / 0.01 = 20

11) I think the answer is lens