Question

1. Parallel light rays pass through a converging lens and

a. stay parallel

b. all travel to a point that is at a defined distance away from the lens

c. diverge rapidly

d. reflect back to a point in front of the lens

2. For a lens with a given focal length of 10 cm and an object placed 15 cm in front of it, where is the image located?

a. 30 cm

b. 10 cm c. 20 cm

d. 25 cm

3. For problem number 2, what is the magnification?

a. M = 1/2

b. M = -1/2

c. M = 2

d. M = -2

4. For problem number 2, describe the relation of the image height to the object height. Is the

a. image height smaller than the object height

b. image height larger than the object height

c. image height and object height are equal

5. Describe the image that is formed in problem #2. Is it?

a. real and upright

b. real and virtual

c. real and inverted

d. virtual and inverted

6. For a lens with a given focal length of 10 cm and an object placed 5 cm in front of it, where is the image located?

a. 10 cm behind the lens

b. 10 cm in front of the lens

c. 2 cm in front of the lens

d. 2 cm behind the lens

7. For problem number 6, what is the magnification?

a. M = ½

b. M = -1/2

c. M = 2

d. M = -2

8. The letter “B” in the above diagram of a camera is identified as the

a. film

b. shutter

c. lens

d. aperture

9. The letter “D” in the above diagram of a camera is identified as the

a. film

b. shutter

c. lens

d. aperture

10. To create a virtual magnified image of an object,

a) the object must be at the focal point of a concave lens.

b) the object must be just outside the focal point of a convex lens.

c) the object must be very far from a convex lens.

d) the object must be within the focal point of a convex lens.

Answer 1

1. Parallel light rays pass through a converging lens and

b. all travel to a point that is at a defined distance away from the lens (to focus)

one can get it from law of refraction.

2. For a lens with a given focal length of 10 cm and an object placed 15 cm in front of it, where is the image located?

a. 30 cm

f = +10 and u = -15

  

3. For problem number 2, what is the magnification?

Magnification for lens is M = v/u = 30 / (-15) = -2

d. M = -2

4. For problem number 2, describe the relation of the image height to the object height. Is the

b. image height larger than the object height

Image is magnified by twice M = v/u = h_i/ho.

5. Describe the image that is formed in problem #2. Is it?

c. real and inverted

6. For a lens with a given focal length of 10 cm and an object placed 5 cm in front of it, where is the image located?

b. 10 cm in front of the lens

f = +10 cm and u = -5 cm

  

7. For problem number 6, what is the magnification?

c. M = 2

M = v/u = -10/-5 = 2

8. The letter “B” in the above diagram of a camera is identified as the

Diagram missing

9. The letter “D” in the above diagram of a camera is identified as the

Diagram missing

10. To create a virtual magnified image of an object,

d) the object must be within the focal point of a convex lens.