(a) Draw a ray diagram to show the formation of image by a concave lens when an object is placed in front of it.
(b) In the above diagram mark the object distance (u) and the image distance (v) with their proper signs (+ve or –ve as per the new Cartesian sign convention) and state how these distances are related to the focal length (f) of the concave lens in the case.
(c) Find the nature and power of a lens which forms a real and inverted image of magnification –1 at a distance of 40 cm from the optical centre.
Answers
Answer:
Explanation:
(a)
The image formed is – behind the object (on the left side of lens)
- Virtual and erect
- Larger than the object
(b) According to the new Cartesian sign convention the following are the rules-
(i) All the distances are measured from the optical centre of lens
(ii) The distances measured in same direction as that of incident light are taken positive.
(iii) The distances measured against the direction of the incident light are taken negative.
(iv) The distances measured upwards and perpendicular to the principal axis are taken positive, others negative.
The focal length of convex lens is considered positive, for concave lens it is negative.
The relation between u, v and f is given by the lens formula
As both (u) and (v) are negative, the above equation will change to:
(c) given u= -20cmm = -1
magnification m= v/u
→ v=mu
→ = -1 × -20 = 20cm
Thus, v = 20 cm
Now, focal length is given as:
→
→ f = 10cm
Now, we know,
→
Explanation:
here
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Find the mode and the mean of the data quien abuse Compare and tulkepretthe Ituro measumee Vof central tendencyAgelinya6-15
Mumba
Ipaliouts
16 - 25 26- 35 36-446-55 56 -65
6 21 14
23
Find the mode and the mean of the data quien abuse Compare and tulkepretthe Ituro measumee Vof central tendencyAgelinya6-15
Mumba
Ipaliouts
16 - 25 26- 35 36-446-55 56 -65
6 21 14
23
Find the mode and the mean of the data quien abuse Compare and tulkepretthe Ituro measumee Vof central tendency
