Two convex lenses of an astronomical telescope have focal length 1.3 m and 0.05 m respectively. Find the magnifying power and the length of the telescope.
1. Telescopes used to see the objects on the Earth, like mountains, trees, players playing a match in a stadium, etc. are called terrestrial telescopes.
2. In such case, the final...
1. A lens is said to be convex if it is thicker in the middle and narrowing towards the periphery. According to Cartesian sign convention, its focal length is positive.
2....
Given: f = 2 cm, v = D = 25 cm
To find: Magnifying power (M.P.)
Formula: M.P = 1 + \(\frac{D}{f}\)
Calculation:
From formula,
M.P = 1 + \(\frac{25}{2}\)
M.P. = 1 + 12.5 = 13.5
Given that, f = +10 cm, u = -8 cm,
From thin lens formula,
\(\frac{1}{f}=\frac{1}{\text{v}}-\frac{1}{u}\)
∴ \(\frac{1}{10}=\frac{1}{\text{v}}-\frac{1}{-8}\)
∴ v = 40 cm
Magnification of a lens is,
m = \(\frac{v}{u}=\frac{Object\,size\,h-i}{Object\,size\,h-0}\)
∴ \(\frac{40}{8}=\frac{h_1}{0.5}\)
∴ h1 = 2.5 cm
This implies the height of the...
Given: f0 = 1 m, L = 1.05 m
To find:
i. Focal length of eyepiece (fe)
Magnifying power under normal adjustment (M)
Formula:
i. L = f0 + fe
ii. M = \(\frac{f_0}{f_e}\)
Calculation: From formula (i),
fe = L – f0 =...
