Answer: f=150cm in water and f=60cm in air.
Explanation: Focal length is a measurement of how strong light is converged or diverged by a system. To find the variable, it can be used the formula:
= (nglass - ni)(
- 
).
nglass is the index of refraction of the glass;
ni is the index of refraction of the medium you want, water in this case;
R1 is the curvature through which light enters the lens;
R2 is the curvature of the surface which it exits the lens;
Substituting and calculating for water (nwater = 1.3):
= (1.5 - 1.3)(
- 
)
= 0.2(
)
f = 
= 150
For air (nair = 1):
= (1.5 - 1)( - )
f = 
= 60
In water, the focal length of the lens is f = 150cm.
In air, f = 60cm.
As the Earth rotates, it also moves, or revolves, around the Sun. ... As the Earth orbits the Sun, the Moon orbits the Earth. The Moon's orbit lasts 27 1/2 days, but because the Earth keeps moving, it takes the Moon two extra days, 29 1/2, to come back to the same place in our sky.
Answer:
30 m/s
Explanation:
Speed is distance over time. 60 meters / 2 seconds, = 30 m/s.
<span>The volcanoes of USA are located along the west coast, at the subduction of the Pacific and North American tectonic plates. During the 20th century there were only two eruptions in continental USA; Lassen in 1915, and Mt St Helens in 1980. Alaska and Hawaii contain currently active volcanoes. hope this helps:)</span>
The elements is group 18 on the periodic table are called "Nobel Gases".
