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 )
ANSWER
T₂ = 10.19N
EXPLANATION
Given:
• The mass of the ball, m = 1.8kg
First, we draw the forces acting on the ball, adding the vertical and horizontal components of each one,
In this position, the ball is at rest, so, by Newton's second law of motion, for each direction we have,

The components of the tension of the first string can be found considering that they form a right triangle, where the vector of the tension is the hypotenuse,

We have to find the tension in the horizontal string, T₂, but first, we have to find the tension 1 using the first equation,

Solve for T₁,

Now, we use the second equation to find the tension in the horizontal string,

Solve for T₂,

Hence, the tension in the horizontal string is 10.19N, rounded to the nearest hundredth.
Answer:
Differences between freefall and weightlessness are as follows:
<h3>
<u>Freefall</u></h3>
- When a body falls only under the influence of gravity, it is called free fall.
- Freefall is not possible in absence of gravity.
- A body falling in a vacuum is an example of free fall.
<h3>
<u>Weightlessness</u></h3>
- Weightlessness is a condition at which the apparent weight of body becomes zero.
- Weightlessness is possible in absence of gravity.
- A man in a free falling lift is an example of weightlessness.
Hope this helps....
Good luck on your assignment....
- Gravitational force depends only on mass and distance, not on the state of matter.
- The forces of attraction between molecules in matter are electromagnetic in nature, not gravitational.
- These attractive forces are stronger in a solid than in a liquid than in a gas.
- Gravitational forces between molecules is completely negligible compared to the em forces.
So, key answer is inter-molecular forces of solids is stronger than liquids.