How do you write a letter to the editor?
Open the letter with a simple salutation. ...
Grab the reader's attention. ...
Explain what the letter is about at the start. ...
Explain why the issue is important. ...
Give evidence for any praise or criticism. ...
State your opinion about what should be done. ...
Keep it brief. ...
Sign the letter.
Kepler's 3rd law is given as
P² = kA³
where
P = period, days
A = semimajor axis, AU
k = constant
Given:
P = 687 days
A = 1.52 AU
Therefore
k = P²/A³ = 687²/1.52³ = 1.3439 x 10⁵ days²/AU³
Answer: 1.3439 x 10⁵ (days²/AU³)
That's two different things it depends on:
-- surface area exposed to the air
AND
-- vapor already present in the surrounding air.
Here's what I have in mind for an experiment to show those two dependencies:
-- a closed box with a wall down the middle, separating it into two closed sections;
-- a little round hole in the east outer wall, another one in the west outer wall,
and another one in the wall between the sections;
So that if you wanted to, you could carefully stick a soda straw straight into one side,
through one section, through the wall, through the other section, and out the other wall.
-- a tiny fan that blows air through a tube into the hole in one outer wall.
<u>Experiment A:</u>
-- Pour 1 ounce of water into a narrow dish, with a small surface area.
-- Set the dish in the second section of the box ... the one the air passes through
just before it leaves the box.
-- Start the fan.
-- Count the amount of time it takes for the 1 ounce of water to completely evaporate.
=============================
-- Pour 1 ounce of water into a wide dish, with a large surface area.
-- Set the dish in the second section of the box ... the one the air passes through
just before it leaves the box.
-- Start the fan.
-- Count the amount of time it takes for the 1 ounce of water to completely evaporate.
=============================
<span><em>Show that the 1 ounce of water evaporated faster </em>
<em>when it had more surface area.</em></span>
============================================
============================================
<u>Experiment B:</u>
-- Again, pour 1 ounce of water into the wide dish with the large surface area.
-- Again, set the dish in the second half of the box ... the one the air passes
through just before it leaves the box.
-- This time, place another wide dish full of water in the <em>first section </em>of the box,
so that the air has to pass over it before it gets through the wall to the wide dish
in the second section. Now, the air that's evaporating water from the dish in the
second section already has vapor in it before it does the job.
-- Start the fan.
-- Count the amount of time it takes for the 1 ounce of water to completely evaporate.
==========================================
<em>Show that it took longer to evaporate when the air </em>
<em>blowing over it was already loaded with vapor.</em>
==========================================
*heat transfer energy, As it always flow from higher temperature to lower temperature till it reach the thermal equilibrium.
example: -friction.
- collisions.
- the hot cup which's hotter than your hand✋will transfer heat in your hand. and a cold piece of ice which's colder than your hand to causing the heat transfer out of your hand .
*temperature ️ depends on the move of particle and we have a different shape of motion like:
translational motion.
rotational motion.
vibrational motion.
when the temperature:
increases it has more kinetic energy and faster moving particles and the object expanded which known as (thermal expansion).
decreases it has less kinetic energy and slower moving particles.
As kinetic energy is 1/2 mV².
example: -the mercury in thermometers.
*Absolute zero :
The theoretical temperature at which substances possess no thermal energy, equal to 0 K, −273.15°C, or −459.67°F.
*specific heat "c" :
is essentially a measure of how thermally insensitive a substance is to the addition of energy.
c=Q/m∆T
where Q is energy .
note water has a higher specific heat, and lower temperature.
*conduction <em><u>example</u></em> When the stove is turned on, the skillet becomes very hot due to the conduction of heat from the burner to the skillet.
