Answer:
3.8 kg
Explanation:
The torque, <em>τ</em>, due to the force, <em>F</em>, is given by

where <em>r</em> is the radius.
This torque is also given by

where <em>I</em> and <em>α</em> are respectively the moment of inertia and the angular acceleration.
For a solid disk, its moment of inertia for an axis though its centre and perpendicular to its face is given by

where <em>m</em> is its mass and <em>r</em> is its radius.
Hence, we have


Answer:
option E
Explanation:
given,
I is moment of inertia about an axis tangent to its surface.
moment of inertia about the center of mass
.....(1)
now, moment of inertia about tangent

...........(2)
dividing equation (1)/(2)



the correct answer is option E
Answer:
Explanation:
a )
The Gaussian surface must have contained both the charges like +3 nC and - 3 nC , total charges being zero . According the Gauss's law , total electric flux over a closed surface is equal to 1 / ε₀ times the total charge contained inside the closed surface .
Since total charge inside is zero , total flux will be 1 / ε₀ x 0 = 0
b )
In this case the Gaussian surface is so small that it contains only the charge
+ 3 nC .
So electric flux over the Gaussian surface
= ( 1 / ε₀ ) x 3 x 10⁻⁹
= (1 / 8.85 x 10⁻¹² ) x 3 x 10⁻⁹
= 3 x 10³ / 8.85
= 339 weber.
=
A) Sunlight basically consists of a combination of light of different wavelengths. Each of these wavelengths correspond to each of the colors of the rainbow. For example, red light has the longest wavelength. This is followed by orange, then yellow, green, blue and indigo. Violet has the shortest wavelength. These wavelengths (750 nm to 400 nm) constitute the visible colors. All these light components of different wavelengths combine together to become the color white.
b) When this sunlight passes through droplets of rain, it gets refracted and that is what breaks up the white light into individual colors of the rainbow, just how light passing through a glass prism gets broken down into its individual seven colors.
c) Different objects have the ability to absorb different wavelengths of light. For example, glass absorbs light of all wavelengths except those between 560-520nm, which corresponds to green light. So it reflects the green light and thus, our eyes see grass as green in color.
d) Light of wavelength below 400 nm (ultraviolet) and above 750nm (Infrared) are not visible. However, they exist in the sun's radiation. Ultraviolet rays are very harmful and responsible for causing sunburn and some types of skin tumors. Infrared light is also harmful and can cause premature wrinkling of skin.