Use the worked example above to help you solve this problem...

Use the worked example above to help you solve this problem. A converging lens of focal length 8.1 cm forms images of an object situated at various distances. (a) If the object is placed 24.3 cm from the lens, locate the image, state whether it's real or virtual, and find its magnification. (If either of the quantities evaluate to infinity, type INFINITY.) q = cm M = (b) Repeat the problem when the object is at 8.1 cm. q = cm M = (c) Repeat again when the object is 4.05 cm from the lens. q = cm M = Suppose the image of an object is upright and magnified 1.70 times when the object is placed 12.8 cm from a lens. Find the location of the image and the focal length of the lens. q = cm f = cm

Transcript

00:01 Hi students in this question, a converging length which is having a focal length f to be equal to 8 .1 centimetre is being given and the first part of the question we are as to find out the image distance v as well as magnification m of this particular lens with the value of object distance u to be equal to 24 .3 cm.

00:22 First we can find out the value of v which can be found out using the lens formula according to which you get 1 by f to be equal to 1 by v plus 1 by u now by substituting the value of focal length and the object distance we get 1 by v to be equal to 1 divided by 8 .1 minus 1 divided by 24 .3 now by simplification we get the value of v to be equal to 12 .15 centimeter next we can find out the value of magnification where the magnification m will be equal to ratio of minus value of of b divided by u now by substituting the value of u and b in this equation we get m to be equal to minus 12 .15 divided by 24 .3 from which we get the value of magnification m to be equal to minus 0 .5.

01:19 Now in the second part of the question also we are asked to find out the value of b as well as magnification m for a given value of u to be equal to 8 .1 centimeter.

01:29 Now in order to to find the value of v, we have to use the lens formula which is given as 1 by v to be equal to 1 by f minus 1 by 1 by u.

01:38 Now by substituting the values we get 1 by v to be equal to 1 divided by 8 .1 minus 1 divided by 8 .1 which on simplification gives the value of v to be equal to a value of infinity.

01:53 Next we can find out the value of magnification m which is equal to negative the value of v divided by u.

01:59 Now since the value of v is taken to be a value of minus infinity divided by 8 .1, we get the value of magnification m to be equal to a value of infinity.

02:11 And the third part of the question also, we are asked to find out the value of v as well as m for a given value of u to be equal to 4 .05 cm...

Question

Please give Ace some feedback