Answer:
Explanation:
Field due to a charge = k x Q / d²
field due to positive charge
=9 x 10⁹ x 4 x 10⁻⁹ / 1x1 = 36 N/C in positive x -direction.
Field due to negative charge
= 9 x 10⁹ x 2 10⁻⁹ / 3² = 2 N/C in positive x-direction.
Total field = 36 +2 = 38 N/C .
Answer: The coefficient of kinetic friction is μ = 0.6
Explanation:
For an object of mass M, the weight is:
W = M*g
where g is the gravitational acceleration: g = 9.8m/s^2
And the friction force between this object and the surface can be written as:
F = W*μ
where μ is the coefficient of friction (kinetic if the object is moving, and static if the object is not moving, usually the static coefficient is larger)
In this case, the weight is:
W = 20N
And the friction force is:
F = 12N
Replacing these values in the equation for the friction force we get:
12N = 20N*μ
(12N/20N) = μ = 0.6
The coefficient of kinetic friction is μ = 0.6
A matchstick has a lot of chemical energy stored in it. When the match is struck, it burns and the chemical energy in it produces heat energy and light energy.
A car acting as an object in front of a biconvex lens between F and 2 F on the object side of the lens. There is a light ray parallel to the principal axis that is bent through F on the image side of the lens. There is a ray straight through the center of the lens. The rays intersect below the x axis further than 2 F away from the lens and farther from the principal axis than the object is tall.
<u> The image produced by the lens is (b) inverted and real</u>
Explanation:
A real image occurs where the rays converge.
Real images can be produced both by the concave mirrors or converging lenses, but the condition is that the object of consideration is always placed far away from the mirror or the lens than the focal point, and thus the real image produced is inverted.
A car acting as an object in front of a biconvex lens between F and 2 F on the object side of the lens. There is a light ray parallel to the principal axis that is bent through F on the image side of the lens. There is a ray straight through the center of the lens. The rays intersect below the x axis further than 2 F away from the lens and farther from the principal axis than the object is tall.
<u> The image produced by the lens is (b) inverted and real</u>
Answer:
If you punched thousands of holes in the aluminum foil, you would see thousands of small images in the viewer.
Explanation:
If thousands of holes is punched/perforated in an aluminum foil, such that there were more holes than foil.
Thousands of small images would be formed, which can be seen in the viewer. Aluminum foil has a good reflective property which allows the thousands of holes punched to reflect equal number of images, although the images are smaller in size than the original image size.
