Answer:
The answer is D- Coal is set aside to burn as heating fuel
Explanation:
Allocation decisions set aside resources for a specific purpose.
Answer:
Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive the Sun's most direct rays. So, when the North Pole tilts toward the Sun, it's summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, it's winter in the Northern Hemisphere.
Answer:
The quantity of energy per photon is inversely proportional to the wavelength of the light.
Explanation:
Energy of light is given as
E = hf
where E = energy of the photons,
f = frequency of the light
If the number of photons = n
(E/n) = (h/n) f
Let (E/n) = E'
(h/n) = h'
But the frequency of light is related to wavelength through the relation
v = fλ
where v = speed of light = c
λ = wavelength of light
f = (c/λ)
E' = h' f
Substituting for f
E' = h' (c/λ)
h' and c are both constants, h'×c = K
E' = (K/λ)
So, the quantity of energy per photon is inversely proportional to the wavelength of the light.
Hope this Helps!!!
Answer:
B
Explanation:
Electromagnetic spectrum includes visible light which we see all the time reflecting off objects to give them colours, mechanical waves like sound require something to move in, its the reason why people say you can't scream in space because space is a giant vacuum. No not the kind you use to clean up the mess you made from breakfast. The kind that has no air. So sound can be heard on earth as it is not a vacuum, air moves freely and transfers sounds vibrations all around you to be absorbed by walls and other stuff in comes in contact with.
Extra information:
Sound travels further in water because the molecules are closer together meaning that transferring the energy is easier. This is how Blue wales can communicate from hundreds of miles away.
Answer:
The velocity relative to the surface of the ice is 6.5 m/s.
Explanation:
Given that,
Mass of girl m= 45.0 kg
Mass of plank M= 150 kg
Velocity = 1.50 m/s
We need to calculate the velocity relative to the surface of the ice
Using conservation of momentum
Here, 
because plank at rest
Put the value into the formula
Hence, The velocity relative to the surface of the ice is 6.5 m/s.
