Click to Chat
1800-1023-196
+91-120-4616500
CART 0
Use Coupon: CART20 and get 20% off on all online Study Material
Welcome User
OR
LOGIN
Complete Your Registration (Step 2 of 2 )
Diameter of a Plano-convex lens is 6 cm and the thickness at the center is 3 mm. If the speed of light in the material of the lens is 2 x 10^8 m/sec, what is the focal length of the lens?
diameter = 2 Radius (R) 2R = 6 R = 3cm 1/f = (u-1)/R ......1 this is the relation bw focal length of plano convex lens & u(refractive index) ... u = c/v = 3*108/2*108 = 1.5 now put u in eq 1 , will get focal length
diameter = 2 Radius (R)
2R = 6
R = 3cm
1/f = (u-1)/R ......1
this is the relation bw focal length of plano convex lens & u(refractive index) ...
u = c/v = 3*108/2*108 = 1.5
now put u in eq 1 , will get focal length
radius will be 15 not 3! use geometry. let (x) be radius of curvature .BASE- (x-3) HEIGHT -(3) HYPOTANEOUS -(x) solve and get (x)! :)
Post Question
Dear , Preparing for entrance exams? Register yourself for the free demo class from askiitians.
points won -