Answer: False
Explanation:
Relative to the concept of radiations, a black body is an object capable of absorbing any form of electromagnetic radiation irrespective of its frequency or angle of incidence when incident on such object.
However, the same cannot be said about real bodies as real bodies are those which reflect all rays incident on them completely and uniformly in all directions.
One very important characteristic of black bodies is that they are ideal emmiters.
The concept of emmisivity is brought about by the existence of real bodies .
This is due to the fact that they are only able to emit radiation at a fraction of the black body energy levels.
Please note that by convention, the emmisivity of a real body is always less thaan 1.
As such they are not able to emit as much radiation as a black body at the same temperature.
Answer:
Trophosphere
Explanation:
The troposphere is the atmospheric layer closest to the planet and is characterized because contains the largest percentage of the mass of the total atmosphere.
On special characteristic is that in this layer the temperature and water vapor content decrease a lot respect to the altitude. Also on this layer the Water vapor is important in order to regulate the air temperature since on this zone we have absorption of the solar energy.
The troposphere contains almost all the water vapor in the atmosphere. And specially on the tropics we have an accumulation of the water vapour.
All weather phenomena occur within the troposphere. Tropos means "change" and Troposphere means "region of mixing".
Above this layer, we have the tropopause, ranges in height from 5 miles near the poles up to 11 miles above the equator. And the height depends of the seasons, with an special characteristic: the is highest height occurs in the summer and lowest height occurs in the winter.
The troposphere contains almost 75% of the mass of the entire atmosphere. The air on this layer is composed by 78% nitrogen, 21% oxygen and 1% is made of argon, water vapor, and carbon dioxide.
So for this reason this is the Region that contains the majority of molecules in the atmosphere.
Answer;
=84 kwh
Explanation;
Electrical energy = 1000 watts
1000 watt = 1 kilo watt
1 week = 7 days
Number of hours = 7 × 12× = 84 hours
Consumption
= 1 kw × 84 hours
= 84 kwh
Think of it this way: If you test only one variable then you know that the difference in the experimental and control setup is that one independent variable. If you test more than one you will not know which one made the difference. Hope this helps :)
Answer:
1.8 x 10⁻³⁴ m.
Explanation:
de Broglie wavelength ( λ ) of a moving particle is given by the following expression
λ = h / momentum of the particle
In other words, de Broglie wavelength depends upon the momentum of the particle.
In the given case , particle A which is stationary collides with another particle B having some momentum . After the collision , they move together.No external force acts on them . Therefore after the collision , their momentum will be conserved. In other words , their momentum remains the same as earlier. So their de Broglie wave length will also be the same as earlier , since it depends on the momentum of the moving body.
Hence the de Broglie wavelength of the object will be 1.8 x 10⁻³⁴ m.