Entry Test MCQ :: Optical Instruments
|
|
|
|
|
11. |
Magnifying power of simple microscope |
A. |
increase with increase in focal length |
B. |
increase with decrease in focal length |
C. |
no effect with decrease or increase with focal length |
D. |
list distance of distinct vision |
Answer: Option B
Explanation:
|
12. |
Image of an object 5 mm high is only 1 cm high. Magnification produced by lens is |
Answer: Option D
Explanation:
|
13. |
The least distance of distinct vision for a normal eye is |
Answer: Option B
Explanation:
|
14. |
Least distance of distinct vision |
A. |
increases with increase in age |
B. |
decreases with increase in age |
C. |
neither increases nor decreases |
D. |
becomes infinite after 60 years |
Answer: Option A
Explanation:
|
15. |
If a convex lens of large aperture fails to converge the light rays incident on it to a single point, it is said to suffer from |
A. |
chromatic aberration |
B. |
spherical aberration |
C. |
both spherical and chromatic |
D. |
distortion |
Answer: Option B
Explanation:
|
16. |
Two convex lenses of equal focal length f are placed in contact the resultant focal length of the combination is |
Answer: Option D
Explanation:
|
17. |
A convex lens of focal length f1 and a concave lens of focal length f2 are placed in contact. The focal length of the combination is |
A. |
f2 + f1 |
B. |
f2 - f1 |
C. |
f1f2/f2+f1 |
D. |
f1f2/f1-f2 |
Answer: Option D
Explanation:
|
18. |
Final image produced by a compound microscope is |
A. |
real and inverted |
B. |
real and erect |
C. |
virtual and erect |
D. |
virtual and inverted |
Answer: Option D
Explanation:
|
19. |
For normal adjustment, length of astronomical telescope is |
A. |
fo + fe |
B. |
fo - fe |
C. |
fo / fe |
D. |
fe / fo |
Answer: Option A
Explanation:
|
20. |
In multimode step index fibre the refractive index of core and cladding is |
A. |
same |
B. |
different |
C. |
zero |
D. |
different with refractive index of core higher than cladding |
Answer: Option D
Explanation:
|
Read more:
|
|