The US Department of Energy has set its own targets to achieve 15% of the country's electricity from hydropower by 2030 — it is currently 7%. Elsewhere around the world, countries are pledging to meet more and more of their energy needs through renewable energy sources.
The first one is an opinion though the second could be too it is for sure the first
Answer:
1 / f = 1 / o + 1 / i
1 / image distance + 1 / object distance = 1 focal length
If the object distance is large the image will be at about the focal length
The value of 1 / f is fixed for any one particular lense
As the object distance decreases the image must increase
The above equation can also be written as
o i / (i + o) = f or i / (i / o + 1) = f
If for instance o was very large the image would be at the focal length
Answer:
Explanation:
We shall convert the displacement in vector form using unit vector i and j
consider east as x axis and north as y axis
170 km at 68.0° east of north
D₁ = 170 sin68 i + 170cos 68 j
= 157 i + 63.68 j
230 km at 36.0° south of east
D₂ = 230 cos36 i - 230 sin 36 j
= 186 i - 135.2 j
Resultant Displacement = D₁ +D₂
= 157 i + 63.68 j + 186 i - 135.2 j
= 343 i - 71.52 j
Resultant magnitude
= √ ( 343² + 71.52²
= 350 km
Angle
= tan⁻¹ ( - 71.52 / 343 )
12⁰ south of east .
Answer:
48%
Explanation:
The earth's temperature has to be stable and this is the reason for the presence of incoming and outgoing heat. Of the solar energy reaching the atmosphere, about 29% is bounced back as reflected radiation by clouds, snow and particles in the atmosphere, about 23% is absorbed by the atmosphere and about 48% actually gets to the earth surface.
