Answer:
Explanation:
a )
from lens makers formula
f is focal length , r₁ is radius of curvature of one face and r₂ is radius of curvature of second face
putting the values
1.462 = 2 - 1 / r₂
1 / r₂ = .538
r₂ = 1.86 cm .
= 18.6 mm .
b )
object distance u = 25 cm
focal length of convex lens f = 1.8 cm
image distance v = ?
lens formula
.5555 - .04
= .515
v = 1.94 cm
c )
magnification = v / u
= 1.94 / 25
= .0776
size of image = .0776 x size of object
= .0776 x 10 mm
= .776 mm
It will be a real image and it will be inverted.
Explanation :
(1) Involuntary muscles are the muscles that are not controlled by our will.
(2) Tendons are the connective tissues that join the muscle to bones. Tendons are tissues that have fibers.
(3) Cardiac muscle is also involuntary muscles. For example heart muscle. It shows contraction and relaxation throughout life.
(4) Voluntary muscle is the muscles that are not controlled by our will.
(5) Biceps are the arm muscles.
Hence, this the required explanation as per options.
<h2>
Answer: Diffraction</h2><h2 />
Diffraction is a characteristic phenomenon that occurs in all types of waves
.
In this sense, <u>diffraction</u> happens when a wave (the light in this case) meets an obstacle or a slit .When this occurs, the light bends around the corners of the obstacle or passes through the opening of the slit that acts as an obstacle, forming <u><em>multiple patterns</em></u> with the shape of the aperture of the slit.
Note that the principal condition for the occurrence of this phenomena is that <u>the obstacle must be comparable in size (similar size) to the size of the wavelength.
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Explanation :
Absorption coefficient of a material determines how much sound is absorbed by the material.
To build a soundproof room, Heavy curtains and carpet can be used. They reduce reverberation.
Reverberation means an echoing sound which persists for some time. For example, when we bang on a huge piece of metal, we hear the reverberation even after we stop banging.
Hence, option (A) and (D) are correct.
