Sarah Garee

Physics 1010

Professor Schaffer

18 June 2019

Class Project

Part 1: Star Identification

Name Distance from Earth(In light years)

Year when light left the star

Size compared to the Sun(1.989 x 10^30)

Luminosity compared to the Sun (382.8)

Alpha Cygni

Deneb 3,550 1036 BCE 3.779 × 10^31 kg

+31617.2

Beta Cygni

Albiero Albiero A: 430Albiero B: 400

Albireo A: 1589Albiero B: 1619

Albireo A: 9.945 × 10^30 kg Albiero B: 6.365 × 10^30 kg

Albiero A: +817.2Albiero B:-152.8

Gamma Cygni

Sadr 1832.38 187 2.409 × 10^31 kg

+3223.6

Epsilon Cygni

Aljanah 72.71 1946 -320.07

Part 2: Equation Analysis

Equation 1: E = mc^2

Question 1: Find out what the things in this equation (using your book or a net

search will do it) are and identify them as either variables or constants.

● E= energy m=mass c^2=speed of light squared

Question 2: What is the size of c^2?

● It’s the speed of light multiplied by itself. c^2=(9x10^16)^2 meters per second

Question 3: Are mass and energy related? Answer yes or no and then provide a

brief explanation of your answer based on the analysis of the equation.

● Yes, they are directly proportional. If the energy were to increase so would the

mass. And if the mass would increase so would the energy.

Question 4: Analyze the statement: “if it is possible to change mass into energy

a little bit of mass could produce a lot of energy”. Is it true or not? Provide a brief

explanation based on your analysis of the equation.

● Technically if it was possible, a little bit of mass would produce a lot of energy

because mass gets multiplied by the constant c^2= (9x10^16)^2. Proving that

this statement, if possible, is true.

Equation 2: d = gt2/2

d = distance an object falls when released from rest (no air resistance)g = acceleration of gravity at the Earth’s surfacet = time the object has been falling

Question 5: Which of the following statements do you agree with and why? Use the equation to support your answer (you can also refer to the learning from equations module files).

a) heavy objects fall faster than lighter objectsb) objects fall at the same speed (if no air resistance) and weight doesn’t

matter

● objects fall at the same speed (if no air resistance) and weight doesn’t mattera. I agree with this statement because the equation does not consider

weight. It only includes the distance an object falls(d), acceleration of gravity(g), and the time the object has been falling(t).

Equation 3: v = gt

v = velocity of a falling object if released from rest (no air resistance)g = acceleration of gravity at Earth’s surfacet = time the object has been falling

Question 6: Which of the following statements do you agree with and why? Use the equation to support your answer (you can also refer to the learning from equations module files)

a) heavy objects fall faster than lighter objectsb) objects fall at the same speed (if no air resistance) and weight doesn’t

matter

● Objects fall at the same speed (if no air resistance) and weight doesn’t matter○ An object's velocity depends on the amount of time it is falling and the

acceleration due to gravity. Similar to the last question, the object's mass or weight doesn’t matter for this equation.

Question 7:For most of recorded history, people thought that heavy objects naturally and under all conditions fall faster than lighter objects. Why did it take us so long to realize the true state of affairs?

● It would make sense that something that is heavier would fall at a faster rate than something lighter. Without further experiments and examination it would be hard to see what is actually going on. Because under the right conditions a bowling ball and a feather would fall at the same rate if there was no air resistance.

Question 8:The Earth’s gravity DOES exert a greater force on heavier objects than lighter ones (these forces are called weight). However, with no air resistance objects fall at the same speed in a given gravity field. The weight difference can be thousands of pounds to one and the objects still fall at the same speed. What physical property of mass compensates for the difference in applied forces?

● It is the physical property of inertia.

Equation 4: e = 1 – Tcold/Thot

e = efficiency of energy useTcold = the temperature of the environment surrounding the heat engineThot = the internal operating temperature of the engine

This is the equation for the efficiency of a heat engine (your car is a heat engine unless you have an electric model). An e = 1 is 100% efficiency, meaning 100% of the energy gets used to do what you want to do with no “wasted”, unrecoverable energy. An e = 0 is an efficiency of zero with none of the energy going to what you want to do and all of the energy being “wasted” or in unrecoverable forms.

Question 9:Is it possible to achieve 100% efficiency, in theory, by lowering the temperature of the environment surrounding the heat engine (Tcold)? Why or why not?

● Yes, in theory. If Tcold was equal to zero, “e” or the efficiency would equal 1 or 100%

Question 10: Is it possible, in practice, to achieve 100% efficiency by lowering the temperature of the environment surrounding the heat engine (Tcold)? Why or why not?

● No, because you can’t maintain the temperature absolute zero.

Question 11: Is it possible to achieve 100% efficiency, in theory, by raising the internal operating temperature of the heat engine (Thot)? Why or why not?

● In theory, yes only if T-hot = infinity

Question 12: Is it possible to achieve 100% efficiency, in practice, by raising the internal operating temperature of the heat engine (Thot)? Why or why not?

● No, because you can’t maintain and infinite amount of heat.

Question 13:If your car is not electric, it is a heat engine and is subject to the efficiency equation. Is it possible to build a car, using any kind of burning fuel, that is 100% efficient? Explain

● No. The second law of thermodynamics states that there is no heat engine that can convert all the heat it has into mechanical energy. The rest just gets released.

Part 3: Learning about a Law of Physics

Pick any Law or Principle of Physics in your textbook and:

1. Give me an explanation of what it is and what it means.

a. Newton’s First Law of Motion: Every object continues in a state of rest or

uniform speed in a straight line unless acted on by a nonzero net force.

2. Give me 3 examples in the real world involving the law or principle

a. Space probes that move continuously in outer space.

b. A tablecloth that is pulled quickly out from under dishes that are at a state

of rest stay at rest

c. If a ball rolls down a hill it will continue to roll unless friction or another

force acts upon it.

Part 4: Explanation of Fermi’s Paradox and possible resolution

If there is extraterrestrial life out there, “Where are they?” or “Where is

everybody?” This is a question a physicist named Enrico Fermi asked that no one has

been able to answer. Thus the creation of Fermi’s Paradox. With how big and diverse

our galaxy is, how have we not had any encounters with other life? Or if we have, why

isn’t there any evidence of their presence? This is the basis of the paradox. The

observable universe is 90 billion light years in diameter. With there being hundreds of

billions of stars out there and even more planets, there has to be some that are able to

sustain life of some sort. Our Sun is fairly young compared to the age of the universe. In

theory, that means that there are Suns out there with earth like planets that should have

civilizations that are further advanced than us in many ways. With that being said, we

still have not seen any sort of sign or received any signals from other life proving that

they exist.

Possible solutions:

1. Extraterrestrial life causing self extinction.

a. On the rare chance that they too are of the Homosapien species and think

similarly to the way we do they have the chance of causing self extinction.

There have been many times that our world or parts of our world has been

at war. We have the capability of wiping out all human life due to man

made bombs that could erase all proof that we existed. What if this

already happened on another planet and that is the reason why we can’t

see any proof of extraterrestrial existence? Or, they could be totally

different with different ways of thinking. They could be more aggressive for

all we know and didn’t last long enough to advance their technology to

reach out to see other life.

2. They already visited Earth

a. Our Sun is young compared to the rest of the universe. There are

hundreds of billions of stars and trillions of planets. A lot of those planets

have to means to sustain life. There could have been life out there that

was so technologically advanced that could have visited our earth back

when the dinosaurs were around. If all they were to see was dinosaurs

and no signs of intelligent life what would be the point to stay? Or if they

did maybe the meteor that wiped out all of the dinosaurs destroyed all

possible proof that they were here. I think they could have been around in

the early time of man as well. There is a legend that attempts to explain

The Stonehenge, they say the Merlin (the wizard) used a magical rod to

levitate the huge stones weighing over a ton into the places they are now.

Maybe it wasn’t merlin but it was extraterrestrial life leaving proof that they

were here.

3. Intelligent life being too far apart from each other

a. The universe is 90 billion light years in diameter. Even traveling at the

speed of light it is impossible to travel the whole universe in one lifetime

(assuming if there is other life their life spans are not long as well.) A

possible reason we have not seen other life could be that we are on

opposite ends of the universe and never will be able to meet. In theory, if

technology advances enough to travel to closer planets that could possibly

sustain life and spread through the universe we could meet other life at

one point if they too are doing the same thing. The odds of this are highly

unlikely and would take a very long time to accomplish but it is not

impossible.