Answer:
D) 21
Explanation:
When gas absorbs light , electron at lower level jumps to higher level .
and the difference of energy of orbital is equal to energy of radiation absorbed.
Here energy absorbed is equivalent to wavelength of 91.63 nm
In terms of its energy in eV , its energy content is eual to
1243.5 / 91.63 = 13.57 eV. This represents the difference the energy of orbit .
Electron is lying in lowest or first level ie n = 1.
Energy of first level
= - 13.6 / 1² = - 13.6 eV.
Energy of n th level = - 13.6 / n². Let in this level electron has been excited
Difference of energy
= 13.6 - 13.6 / n² = 13.57 ( energy of absorbed radiation)
13.6 / n² = 13.6 - 13.57 = .03
n² = 13.6 / .03 = 453
n = 21 ( approx )
1 g = 1 ÷ 1000 kg
= 0.001 kg
1 cm³ = 1 ÷ 100 ÷ 100 ÷ 100 m³
= 0.000001 m³
1 g/cm³ = 1 g / 1 cm³
= 0.001 kg / 0.000001 m³
= 1000 kg/m³
The density is 1000 kg/m³.
A heat engine would be less efficient due to many factors
For instance, a heat engine is more efficient when it uses in cold weather because there is a greater temperature difference ( Carnot Efficient )
A heat engine could be less efficient because of friction
Hope it helps I am a beginner
Answer:
planting trees - increasing the amount of animal life on earth
Explanation:
from all the other options given, all except planting trees will increase global temperature.
1. deforestation: this removes vegetative cover and the amount of oxygen in the atmosphere.
2. increasing the use of gasoline burning vehicles: burning gasoline produces carbon dioxide which is a green house gas which traps heat in the atmosphere and causes global warming
3. increasing the industrial release of carbon dioxide: carbon dioxide is released when gasoline is burned in industries, this in-turn causes global warming.
Trees produces oxygen and sucks in carbon dioxide which causes global warming. more trees mean more oxygen and less carbon dioxide which translates to less global increase in temperature
Phytophotodermatitis happens when certain plant chemicals cause the skin to become inflamed following exposure to sunlight.
