An object of mass 0.03 kg is displaced from its equilibrium position at x = 0 to a distance x = 40 cm and is then released. The restoring force acting on the object is proportional to its displacement and acts in the opposite direction of the displacement. The period of an oscillating particle is 2.0 sec. Write equations for (a) the position x versus t,

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An object of mass 0.03 kg is displaced from its equilibrium position at x = 0 to a distance x = 40 cm and is then released. The restoring force acting on the object is proportional to its displacement and acts in the opposite direction of the displacement. The period of an oscillating particle is 2.0 sec. Write equations for (a) the position x versus t, (b) the velocity v versus t, (c) the acceleration a versus t, and find (d) the maximum velocity of the particle, (e) the maximum acceleration of the particle and (f) its total energy.
A simple pendulum 2.50 m long swings with a maximum angular displacement of 16°. Find its (a) period of vibrations, (b) frequency of vibrations, (c) linear speed at its lowest point of vibration, and (d) linear acceleration at the end of its path.
A spherical ornament of mass 0.01 kg and radius 0.20 m is doing simple harmonic motion about an axis passing through its surface. It swings back and forth as a physical pendulum. Find its period of oscillation.
A 0.540 kg mass is attached to the end of a spring with force constant k = 300 N/m. The object is displaced and released. A damping force F = −b v acts on the object where b = 7.5 kg/s. (a) Find the frequency of the oscillation of the mass. (b) For what value of b will the motion be critically damped?
The motion of a particle connected to a spring is described by x = 10 sin (πt). At what time (in s) is the potential energy equal to the kinetic energy?
An archer pulls her bow string back 0.40 m by exerting a force that increases uniformly from zero to 240 N. What is the equivalent spring constant of the bow, and how much work is done in pulling the bow?
For the wave described by , determine the first positive x coordinate where y is a maximum when t = 0.
Answer the following questions in as much detail as possible. Once you have completed your post, respond to the post of at least 2 of your classmates. 1. Nikola Tesla, one of the inventors of radio and an archetypal mad scientist, told a credulous reporter in 1912 the following story about an application of resonance. He built an electric vibrator that fit in his pocket, and attached it to one of the steel beams of a building that was under construction in New York. Although the article in which he was quoted didn’t say so, he presumably claimed to have tuned it to the resonant frequency of the building. “In a few minutes, I could feel the beam trembling. Gradually the trembling increased in intensity and extended throughout the whole great mass of steel. Finally, the structure began to creak and weave, and the steelworkers came to the ground panic-stricken, believing that there had been an earthquake. … [If] I had kept on ten minutes more, I could have laid that building flat in the street.” Is this physically plausible? 2. A sound wave that underwent a pressure-inverting reflection would have its compressions converted to expansions and vice versa. How would its energy and frequency compare with those of the original sound? Would it sound any different? What happens if you swap the two wires where they connect to a stereo speaker, resulting in waves that vibrate in the opposite way?

An object of mass 0.03 kg is displaced from its equilibrium position at x = 0 to a distance x = 40 cm and is then released. The restoring force acting on the object is proportional to its displacement and acts in the opposite direction of the displacement. The period of an oscillating particle is 2.0 sec. Write equations for (a) the position x versus t,

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An object of mass 0.03 kg is displaced from its equilibrium position at x = 0 to a distance x = 40 cm and is then released. The restoring force acting on the object is proportional to its displacement and acts in the opposite direction of the displacement. The period of an oscillating particle is 2.0 sec. Write equations for (a) the position x versus t, (b) the velocity v versus t, (c) the acceleration a versus t, and find (d) the maximum velocity of the particle, (e) the maximum acceleration of the particle and (f) its total energy.
A simple pendulum 2.50 m long swings with a maximum angular displacement of 16°. Find its (a) period of vibrations, (b) frequency of vibrations, (c) linear speed at its lowest point of vibration, and (d) linear acceleration at the end of its path.
A spherical ornament of mass 0.01 kg and radius 0.20 m is doing simple harmonic motion about an axis passing through its surface. It swings back and forth as a physical pendulum. Find its period of oscillation.
A 0.540 kg mass is attached to the end of a spring with force constant k = 300 N/m. The object is displaced and released. A damping force F = −b v acts on the object where b = 7.5 kg/s. (a) Find the frequency of the oscillation of the mass. (b) For what value of b will the motion be critically damped?
The motion of a particle connected to a spring is described by x = 10 sin (πt). At what time (in s) is the potential energy equal to the kinetic energy?
An archer pulls her bow string back 0.40 m by exerting a force that increases uniformly from zero to 240 N. What is the equivalent spring constant of the bow, and how much work is done in pulling the bow?
For the wave described by , determine the first positive x coordinate where y is a maximum when t = 0.
Answer the following questions in as much detail as possible. Once you have completed your post, respond to the post of at least 2 of your classmates. 1. Nikola Tesla, one of the inventors of radio and an archetypal mad scientist, told a credulous reporter in 1912 the following story about an application of resonance. He built an electric vibrator that fit in his pocket, and attached it to one of the steel beams of a building that was under construction in New York. Although the article in which he was quoted didn’t say so, he presumably claimed to have tuned it to the resonant frequency of the building. “In a few minutes, I could feel the beam trembling. Gradually the trembling increased in intensity and extended throughout the whole great mass of steel. Finally, the structure began to creak and weave, and the steelworkers came to the ground panic-stricken, believing that there had been an earthquake. … [If] I had kept on ten minutes more, I could have laid that building flat in the street.” Is this physically plausible? 2. A sound wave that underwent a pressure-inverting reflection would have its compressions converted to expansions and vice versa. How would its energy and frequency compare with those of the original sound? Would it sound any different? What happens if you swap the two wires where they connect to a stereo speaker, resulting in waves that vibrate in the opposite way?

PROBLEM ONE Pete meets Eileen for the first time and is immediately attracted to her. If Pete has a mass of 86 kg and Eileen has a mass of 59 kg and they are separated by a distance of 2 m, is their attraction purely physical?

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PROBLEM ONE Pete meets Eileen for the first time and is immediately attracted to her. If Pete has a mass of 86 kg and Eileen has a mass of 59 kg and they are separated by a distance of 2 m, is their attraction purely physical?
PROBLEM TWO What is the value of g at a distance from the earth (Me = 5.98 x 10 24 kg) of two (2) earth radii?
PROBLEM THREE Three 5.0-kg masses are located at points in the xy plane, as shown. What is the magnitude of the resultant force (caused by the other two masses) on the mass at x = 0, y = 0.30 m?
PROBLEM FOUR What is the kinetic energy of a 200-kg satellite as it follows a circular orbit of radius 8.0 x 10 6 m around the Earth? (Mass of Earth = 6.0 x 10 24 kg.)
PROBLEM FIVE An object is released from rest at a distance h above the surface of a planet (mass = M, radius = R < h). With what speed will the object strike the surface of the planet? Disregard any dissipative effects of the atmosphere of the planet. PROBLEM SIX What is the escape speed from a planet of mass M and radius R if M = 3.2 x 10 23 kg and R = 2.4 x 10 6 m? Please be sure to show all your work. Once complete, you should scan your homework and submit the file as an attachment here. If you do not have access to a scanner, please contact your instructorBEFORE THE DUE DATE to make arrangements for another method of submission. PROBLEM SEVEN In a few billion years, the sun will start undergoing changes that will eventually result in its puffing up into a red giant star. (Near the beginning of this process, the earth’s oceans will boil off, and by the end, the sun will probably swallow the earth completely.) As the sun’s surface starts to get closer and close to the earth, how will the earth’s orbit be affected? Complete the following problems: 1. Two kilograms of water at 100°C is converted to steam at 1 atm. Find the work done (in J). (The density of steam at 100°C is 0.598 kg/m3 .) 2. How much heat, in joules, is required to convert 1.00 kg of ice at 0°C into steam at 100°C? (Lice = 333 J/g; Lsteam = 2.26 ´ 103 J/g.) 3. Assume 3.0 moles of a diatomic gas has an internal kinetic energy of 10 kJ. Determine the temperature of the gas after it has reached equilibrium. 4. One mole of helium gas expands adiabatically from 2 atm pressure to 1 atm pressure. If the original temperature of the gas is 20°C, what is the final temperature of the gas? (g = 1.67) 5. A refrigerator has a coefficient of performance of 4. If the refrigerator absorbs 30 cal of heat from the cold reservoir in each cycle, how much heat is expelled (in cal) into the heat reservoir? 6. An 800-MW electric power plant has an efficiency of 30%. It loses its waste heat in large cooling towers. Approximately how much waste heat (in MJ) is discharged to the atmosphere per second? 7. Exactly 500 grams of ice are melted at a temperature of 32°F. (Lice = 333 J/g.) What is the change in entropy (in J/K) ? 8. Answer any two (2) of the following questions in as much detail as possible. Once you have completed your post, respond to the post of at least 2 of your classmates. 1. Why will a refrigerator with a fixed amount of food consume more energy in a warm room than in a cold room? 2. Water put into a freezer compartment in the same refrigerator goes into a state of less molecular disorder when it freezes. Is this an exception to theentropy principle? 3. Comment on the following statement: The second law of thermodynamics is one of the most fundamental laws of nature, yet it is not an exact law at all

Identify the physics principles contained within the following scenario. Explain how these principals connect to Einstein's theory of relativity or in modern applications in physics.

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Identify the physics principles contained within the following scenario. Explain how these principals connect to Einstein’s theory of relativity or in modern applications in physics. If you use a GPS option on your car or a mobile device, you are using Einstein’s theory of relativity. Finally, provide another example from your own experience, then compare and contrast your scenario to the provided example below.
Scenario
Mandy took a trip to Rome, Italy. She gazed out over the open ocean 20,000 feet below as her airplane began its descent to her final destination of Rome. It had been a long flight from New York to Rome, but she as she stretched, and her bones creaked as though she was old, she knew that in fact, she was a tiny bit younger than her compatriots back home, thanks to traveling at hundreds of miles per hour. In fact, time for her was running slowly compared to her friends in New York for two reasons: the speed at which she had traveled and the height of the airplane above the Earth. Neither, though, were noticeable.

Question 1 A car with 60 cm diameter tires is traveling at a constant speed of 100 km/hr. What is the angular velocity of the tires in rad/s?

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Question 1
A car with 60 cm diameter tires is traveling at a constant speed of 100 km/hr. What is the angular velocity of the tires in rad/s?
Question 2
A 3 kg ball is traveling in a circle of radius 2 meters with a tangential velocity of 2 meters/second. Find the centripetal acceleration of the ball and the centripetal force acting on it.
Question 3
An arrow is shot at an angle such that it’s horizontal velocity is 40 m/s and it’s vertical velocity is 20 m/s. Find the horizontal distance the arrow will travel before hitting the ground.
Question 4
A bolt requires 15 Nm or torque to loosen it. How much force needs to be applied to a 20 cm long wrench to loosen the bolt? Assume the force is applied perpendicular to the handle of the wrench.
Question 5
A baseball is thrown such that it is in the air for 4 seconds and lands 100 m away. Find the initial vertical and horizontal components of the baseball’s velocity.

Problem 1.1 A 10cm sphere charged with a car battery (12V), picks up a positive charge of +100pC. How many excess or deficient electrons are on the sphere?

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Problem 1.1 A 10cm sphere charged with a car battery (12V), picks up a positive charge of +100pC. How many excess or deficient electrons are on the sphere?
Select One of the Following:
(a) 3.2× 109 deficient electrons
(b) 1.1× 1014 excess electrons
(c) 6.7× 1011 deficient electrons
(d) 9.5× 105 excess electrons
(e) 6.3× 108 deficient electrons
Homework Problem 1.2 Your standard number 2 mechanical pencil has a graphite lead with mass 0.05g. How many protons are in this quantity of graphite? The atomic mass of carbon is 12g/mole and the atomic number is 6.
Select One of the Following:
(a) 3.1× 1010protons
(b) 1.5× 1022protons
(c) 5.1× 1024protons
(d) 2.3× 1021protons
(e) 6.5× 1023protons
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Homework Problem 1.3 An insulating cylinder has height 5cm and radius 10cm. If it carries a uniform surface charge density σ = −1µC/m2 including the ends, compute the total charge of the cylinder.
Select One of the Following:
(a) Q = −2× 10−2C
(b) Q = −3× 10−4C
(c) Q = −5× 10−6C
(d) Q = −9× 10−8C
Homework Problem 1.4 A problem you should have easily been able to do in Phys 111, but I get asked it all the time when I ask for a good question on electricity and magnetism the first day of class. Suppose a human can confortably live in a spaceship accelerating at 1g = 9.81m
s2 , ignoring relativistic effects, how long does it take
the spaceship to reach the speed of light? Report your answer in years. You may use the approximate conversion 1yr = π × 107s.
Select One of the Following:
(a) 15.7yr
(b) 0.19yr
(c) 0.97yr
(d) 15, 000yr
Homework Problem 1.5 How does the mass of the electron compare with the mass of the proton?
Select One of the Following:
(a) The two masses are equal.
(b) The electron is slightly more massive than the proton.
(c) The electron is slightly less massive than the proton.
(d) The electron is greatly more massive than the proton.
(e) The electron is greatly less massive than the proton.
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Homework Problem 1.6 In the nuclear process “beta decay”, a neutron is converted into some other charged particles, one of which is a proton. Some neutral particles are also emitted. What other charged particle must be emitted in beta decay?
Select One of the Following:
(a) an electron or something with the charge of an electron
(b) two electrons or particles with total charge equal to two electrons
(c) a proton or something with the charge of a proton
(d) an electron and a proton
(e) No other charged particles are required.
Multiple-Choice Questions
Homework Problem 1.7 A patch of positive charge is placed on a conducting sphere. Where will the positive charge be at a later time? Assume no charge is lost to the environment.
Select One of the Following:
(a) The charge will remain in the same place.
(b) The charge will stay bunched together but will move around the surface of the conductor.
(c) The charge will separate as much as possible spreading over the surface of the conductor.
(d) The charge will transform into neutral charge and disappear.
(e) The charge will spread apart, but will eventually come back together.
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Homework Problem 1.8 Which of the following describes an experiment that demonstrates that there are at least two different types of electric charge?
Select One of the Following:
(a) Rub one pair of rods made of the same material – for example, glass – with felt. Observe that the glass rods repel one another.
(b) Charge a pair each of glass and rubber rods by rubbing them with felt. Observe that that (1) the glass rods repel each other, (2) the glass rods attract the rubber rods, and (3) the rubber rods repel each other.
(c) Charge a pair each of glass and quartz rods by rubbing them with felt. Observe that that (1) the glass rods repel each other, (2) the quartz rods repel the glass rods, and (3) the quartz rods repel each other.
Homework Problem 1.9 Can a charged object exert a force on an uncharged insulator? If yes, why; if no, why not?
Select One of the Following:
(a) Yes, by inducing an electrical polarization in the insulator; the insulator is then attracted to the charged object.
(b) Yes, by inducing an electrical polarization in the insulator; the insulator is then repelled by the charged object.
(c) No, because uncharged objects do not feel electrical forces.
(d) No, because only conductors are attracted to or repelled by charged objects.
(e) No, because an insulator does not permit the motion of electric charge.
Homework Problem 1.10 It used to be that one could count on a water pipe as a good “ground”. A “ground” is a continuous conducting path to a long conductor buried in the Earth. Today, plumbing often involves plastic pipes and valves. Explain why this makes a water pipe something we now have to be careful of as a ground.
Select One of the Following:
(a) Plastic is only a conductor part of the time.
(b) The plastic is an insulator and may prevent there from being a continuous path to ground.
(c) Water pipes do not go into the ground anymore and thus won’t be grounded.
(d) The plastic will prevent the water from absorbing the charge.
(e) The plastic will divert any charge going to ground into the water which will shock anyone who uses the water.
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Homework Problem 1.11 Which of the following describes an experiment that demonstrates that there are at least two different types of electric charge?
Select One of the Following:
(a) Rub one pair of rods made of the same material – for example, glass – with felt. Observe that the glass rods repel one another.
(b) Charge a pair each of glass and rubber rods by rubbing them with felt. Observe that that (1) the glass rods repel each other, (2) the glass rods attract the rubber rods, and (3) the rubber rods repel each other.
(c) Charge a pair each of glass and quartz rods by rubbing them with felt. Observe that that (1) the glass rods repel each other, (2) the quartz rods repel the glass rods, and (3) the quartz rods repel each other.
Homework Problem 1.12 After sliding down a plastic slide at the park, your hair stands on end. It continues standing on end even after you get off the slide. What does this imply?
Select One of the Following:
(a) It implies that you have picked up a net charge from the slide.
(b) It implies that your hair has become polarized.
(c) It implies that your hair is covered in water and has become a better conductor.
(d) It implies that your hair has become conducting.
(e) It implies that your hair has become insulating.
Homework Problem 1.13 When an object is grounded, its net charge is reduced to approximately zero. Is this consistent with the Law of Conservation of Charge, if so how?
Select One of the Following:
(a) It is not consistent with conservation of charge; charge is actually destroyed when an object is grounded. Conservation of Charge only applies in some cases.
(b) It is consistent with Conservation of Charge; charge is actually destroyed on the object, but an equivalent charge will be created somewhere else in the universe.
(c) It is consistent with Conservation of Charge; charge is not destroyed but is transferred to another object.
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Homework Problem 1.14 A negatively charged golf tube (plastic rod) is brought near an uncharged conducting bucket. A positively charged pith ball is suspended within the bucket. Select the figure that accurately shows how the pith ball will react.
Select One of the Following:
(a) Figure (a) (b) Figure (b) (c) Figure (c)
GT
conductor
+
_ _
pith
Figure (a)
GT
conductor
+
_ _
pith
Figure (b)
GT
conductor
+
_ _
pith
Figure (c)
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Open Response Questions
All questions in this section must be worked. One of the questions will be graded.
Homework Problem 1.15 A hula-hoop (a circular hoop) has radius 0.6m and linear charge density around its edge of 0.3µC/m. What is the total charge of the hoop in Coulombs?
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Homework Problem 1.16 Since 1982, a penny has contained 2.5grams of copper. The atomic weight of copper is 63.546g/mole and the atomic number is 29. How many electrons are in a penny?
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Homework Problem 1.17 In the following, explain each step carefully and provide a drawing. A Coke can is brought into the electric field of a negatively charged golf tube.
(a)What is the direction of the force on the Coke can and why?
(b)The Coke can is then grounded in the presence of the golf tube. The golf tube had negative charge then what is the sign of the charge on the Coke can?
(c)What is the direction of the force on the Coke can after grounding and why?