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 )
The correct answer is option B, representational
All the painters in Peale family were involved in paintings which represent the day today life activities or were portraits or mimic some natural forms.
Charles Willson Peale , the head of the Peale family was known for painting sixty portraits of the first American president, George Washington. He also painted portraits of portraits of notable people of the society such as Benjamin Franklin, Thomas Jefferson etc.
Most of the paintings of peale family were based on the theme of family, art and science. Six of Peale’s son were known for their renaissance paintings. His oldest son Raphelle was known for still life paintings.
Titian Ramsay Peale, Charles’ youngest son was a naturalist painter.
Answer:
3.6 m
Explanation:


Also


Therefore, the minimum distance L you can place a screen from the double slit that will give you an interference pattern on the screen that you can accurately measure using an ordinary 30 cm (12 in) ruler. = 3.6 m
Answer:
Gametes are the cells used during sexual reproduction to produce a new individual organism.
Explanation:
The male gamete or sperm, is a smaller, mobile cell that meets up with the much larger and less mobile female gamete, egg or ova.
Answer:
Explanation:
Distance travelled by wave = 8 x 2 = 16 m
Time taken = 4 s
velocity of pulse wave = distance / time
= 16 m / 4 s
= 4 m/s