<u>First law of thermodynamics:</u>
- It states that <em>"Energy neither be created nor it can be destroyed". </em>simply it converts one form of energy into another form.
- It is also known as<em> "law of conservation of energy"</em>
<u>Limitations of First law</u>
- It doesn't provide a clear idea about the direction of transfer of heat.
- It doesn't provide the information that how much heat energy converted inti work.
- Its not given any practical applications.
<u>II law of thermodynamics:</u>
It states that <em>"the total entropy of the system can never decrease over time"</em>
It is strongly proved by two laws, they are
<em>1. Kelvin-plank statement:</em>
He stated that "any engine does not give 100% efficiency". It violates the Perpetual motion of machine II kind<em>(PMM-II).</em>
<em>2. Classius statement: </em>
<em> </em><em> It states that "Heat always flows from high temperature body to low temperature body, without aid of external energy". </em>
<em> Also it stated that " Heat can also be transferred from low temperature body to high temperature body, by the aid of an external energy".</em>
<em>Applications of II law: </em>
<em>Refrigeration &Air conditioning, Heat transfer, I.C. engines, etc.</em>
Answer:
the time Joshua travels 1 mile is 12.5 min
Explanation:
Let's start by finding the distance traveled on each lap,
Let's reduce everything to the SI system
R = 400 m
d = 1 mile (1609 m / 1 mile) = 1609 m
L = 2 pi R
L = 2 pi 400
L = 2513 m
Let us form a rule of proportions if 2 turns of Julian is 3 turns Joshua, for 1 turn of Joshua how many turns Julian took
lap Julian = 2/3 turn Joshua
Let's calculate what distance is the same for both of them since they are on the same track
1 lap = 2513 m
d. Julian = 2/3 2513 m
d Julian = 1675 m distance Joshua
Let us form the last rule of three or proportions if 1609 m you travel in 12 min how long it takes to travel 1675 m
t Julian = 1675/1609 12
t = 12.5 s
Since this is the distance Joshua travels, this is the time Joshua travels 1 mile
Answer:
See the answers below.
Explanation:
to solve this problem we must make a free body diagram, with the forces acting on the metal rod.
i)
The center of gravity of the rod is concentrated in half the distance, that is, from the end of the bar to the center there is 40 [cm]. This can be seen in the attached free body diagram.
We have only two equilibrium equations, a summation of forces on the Y-axis equal to zero, and a summation of moments on any point equal to zero.
For the summation of forces we will take the forces upwards as positive and the negative forces downwards.
ΣF = 0
Now we perform a sum of moments equal to zero around the point of attachment of the string with the metal bar. Let's take as a positive the moment of the force that rotates the metal bar counterclockwise.
ii) In the free body diagram we can see that the force acts at 18 [cm] of the string.
ΣM = 0
![(15*9) - (18*W) = 0\\135 = 18*W\\W = 7.5 [N]](https://tex.z-dn.net/?f=%2815%2A9%29%20-%20%2818%2AW%29%20%3D%200%5C%5C135%20%3D%2018%2AW%5C%5CW%20%3D%207.5%20%5BN%5D)
Answer:
7,14545 mph and 3,1936 m/s
Explanation:
The average speed is calculated by dividing the displacement over time, then it is 26,2 miles/(3 2/3 hours), here 3 (2/3) hours is a mixed number, that represents 11/3 hours or 3,66 hours. Then the average speed is 7,14545 mph, now to turn this into meters per second, we notice as mentioned that 1 mile =1609 meters and 1 hour=3600 seconds. Then 7,14545 miles/hour* (1 hour/3600 seconds) * (1609 meters/1 mile)=3,1936 m/s
On mars people would way less.
An example of this is that if I weighed 700 pounds (I don't by the way) I would then weigh 500 pounds or less.
