Space and Time HW

I have attached the HW and need someone to do it CORRECTLY please. DUE TONIGHT.

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Name: _______________________________

Phys 1412 Section: _________________

Space-Time and Building Blocks of the Universe

Objectives:

1. Special and general theory of relativity in sci-fi media.

2. Implication of Quantum Mechanics.

Background

Heisenberg’s Uncertainty Principle states the more that is known about the location of a body, the less can be known about the momentum. And the more that is known about the momentum of a body, the less can be known about the location. Here, “location” and “wavelength” refer to the same thing.

Heisenberg’s Uncertainty Principle can be written mathematically as Δx Δp ≈ h where Δx is the uncertainty in location (or the wavelength), Δp is the uncertainty in momentum, and h is Plank’s constant and e

q

ual to 6.6 × 10-34 J·s. (where 1 J·s = kg·m2/s). (See pages 457 – 458 in the 4th edition of the textbook.)

If I need to find the momentum of an object, I need to know its mass in kilograms (kg) and its velocity in meters per second (m/s). The equation for momentum is p = mv. (See pages 115 – 116 in the 4th edition of the textbook.)

Part I: Sci-fi Movie Review

Read Chapters S2 and S3, and review what we have learned regarding the Special and General Theories of Relativity. Read a book or watch a popular movie on science fiction that involves interstellar travel or time travel. Study it closely as you read/watch it. Write a page long essay (prefer typing) with roughly 250-500 words answering these questions:
(a) What aspects of the movie are consistent with the theories we just learned?
(b) What aspect(s) violate the theory?
(c) How did the character(s) do the travel in space or time?

[Type answer here]

Part II: Quantum Mechanics

Please show your calculations, expressing all quantities in scientific notation. Keep 2 digits for all your results. (Show equation with numbers plugged-in, and the answer either underlined or boxed-in.)

A. Wave Particle Duality and Uncertainty Principle

1.) A small stone has a mass of 1g or 0.001kg. The stone is moving with a speed of 12,000 m/s (roughly the escape speed). The Planck’s constant h is 6.6 × 10-34 J·s. (where 1 J·s = kg·m2/s).

a. What is wavelength of the stone?

b. Comment on why we do not “see” this wave nature of the stone.

[Type answer here]

2.) A baseball is moving at 25 m/s. We use visible light to see the baseball. The uncertainty in determining its position is roughly the wavelength of visible light: 500 nm (500 × 10-9 m).

a.
Use the uncertainty principle to determine the uncertainty in its momentum.

b.
Comment on why the baseball player does not “feel” the uncertainty when determining the baseball’s movement.

[Type answer here]

B. The strong force

In a Helium nucleus, there are two protons. They are very close together; their average distance is 1.2 × 10-15 m.

a.
Estimate the repelling electromagnetic force between the two protons.

b.
What is the force that binds the protons together?

c.
What can you conclude about the strength of the force?

(Fem = k

2
2
1
r
q
q
, where k is a constant equal to 9.0 × 109 N·m2/C2, q1 and q2 are the charge of the protons which each equal 1.6 × 10-19 C, and r is the distance between the two charges)
[Type answer here]

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