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Mars or bust! By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School Have you ever wanted to go to Mars? Sending humans to Mars will require a lot of preparation but the work has already begun. If you were too young to have watched the efforts to send the first humans to the Moon, you may be able to participate in this next big space exploration. This chapter provides some insight into the exploration of Mars. Have you ever wanted to go to Mars? Sending humans to Mars will require a lot of preparation but the work has already begun. If you were too young to have watched the efforts to send the first humans to the Moon, you may be able to participate in this next big space exploration. This chapter provides some insight into the exploration of Mars. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

Book Chapter

Color creation By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School Everyone loves colors—the colors of spring and summer, the colors of butterfly wings and rainbows, the colors of soap bubbles, and the colors from a CD. How are these the same? How are they different? Should we look to the same cause for what appears to be the same effect? The rainbow is arguably Nature’s most beautiful optical display. After a rainfall, the bow of colors can extend from horizon to horizon. The creation of the rainbow involves the...  [view full summary] Everyone loves colors—the colors of spring and summer, the colors of butterfly wings and rainbows, the colors of soap bubbles, and the colors from a CD. How are these the same? How are they different? Should we look to the same cause for what appears to be the same effect? The rainbow is arguably Nature’s most beautiful optical display. After a rainfall, the bow of colors can extend from horizon to horizon. The creation of the rainbow involves the physics of refraction and reflection and a geometry first explained by Descartes. This chapter features the study of colors by Isaac Newton and others who devised some wonderful investigations. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

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The nature of light By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School Light plays such a crucial role in our lives that it’s very hard to imagine a universe without light. But what is light? How do we describe its behavior? We have two basic models that we can use to describe light—particle behavior and light behavior—and the debate over the best way to describe light has been waged for centuries. This chapter features the debates of Newton, Einstein, and Compton, and focuses on a one-dimensional, nonrelativistic...  [view full summary] Light plays such a crucial role in our lives that it’s very hard to imagine a universe without light. But what is light? How do we describe its behavior? We have two basic models that we can use to describe light—particle behavior and light behavior—and the debate over the best way to describe light has been waged for centuries. This chapter features the debates of Newton, Einstein, and Compton, and focuses on a one-dimensional, nonrelativistic derivation of the Compton effect as the basis for the chapter. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

Book Chapter

Do you promise not to tell? By: Arthur Eisenkraft Edited by: Larry D. Kirkpatrick Grade Level: High School Can you keep a secret? Is it possible to send a signal out so that one person will receive the signal but another will not? The scenario presented in this chapter is a young radio amateur who maintains a link with two friends living in two towns. Two antennas are positioned such that when one friend, living in town A, receives a maximum signal, the other friend, living in town B, receives no signal, and vice versa. The two antennas transmit with equal...  [view full summary] Can you keep a secret? Is it possible to send a signal out so that one person will receive the signal but another will not? The scenario presented in this chapter is a young radio amateur who maintains a link with two friends living in two towns. Two antennas are positioned such that when one friend, living in town A, receives a maximum signal, the other friend, living in town B, receives no signal, and vice versa. The two antennas transmit with equal intensities uniformly in all directions in the horizontal plane. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

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Elephant ears By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School Why do elephants have such big ears? And why do they have such thick legs? In other words, why do elephants have different shapes than horses? This chapter focuses on these questions and more explaining how they can be answered using the laws of scaling learned in physics. Why do elephants have such big ears? And why do they have such thick legs? In other words, why do elephants have different shapes than horses? This chapter focuses on these questions and more explaining how they can be answered using the laws of scaling learned in physics. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

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Local fields forever By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School An interesting experiment to perform involves a helium balloon tied to the seat of a car. As the car accelerates forward, the helium balloon will lean forward. There are two distinct ways of explaining why. The first involves the inertia of the air. An acceleration forward compresses the air in the rear of the car. The increased pressure in the rear of the car forces the balloon forward to the area of lower pressure. Just imagine the acceleration...  [view full summary] An interesting experiment to perform involves a helium balloon tied to the seat of a car. As the car accelerates forward, the helium balloon will lean forward. There are two distinct ways of explaining why. The first involves the inertia of the air. An acceleration forward compresses the air in the rear of the car. The increased pressure in the rear of the car forces the balloon forward to the area of lower pressure. Just imagine the acceleration of the car as being equivalent to a gravitational field pointing backward. We can call the vector sum of the gravitational fields the “local field.” Both approaches—pressure differences and local fields—can be used to explain the motion of the helium balloon. This chapter focuses on finding some local fields on an idealized spherical Earth. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

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A physics soufflé By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School What distinguishes the world’s great chefs from the millions of adequate cooks is an understanding of the concepts of cooking. We strive for a similar appreciation of physics concepts in our students. Most of the time the problems in physics textbooks do not require much understanding to obtain the answer in the back of the book. To enhance such a cookbook problem, we may provide superfluous information like the velocity of the object or its color....  [view full summary] What distinguishes the world’s great chefs from the millions of adequate cooks is an understanding of the concepts of cooking. We strive for a similar appreciation of physics concepts in our students. Most of the time the problems in physics textbooks do not require much understanding to obtain the answer in the back of the book. To enhance such a cookbook problem, we may provide superfluous information like the velocity of the object or its color. Students must know the concepts well enough to understand that the velocity and color are not needed. Only the capable chef can ensure that the soufflé will rise. Other examples of providing superfluous information in physics are presented in this chapter. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

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Cool vibrations By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School A low rumble through the Earth convulses a highway like a fish gasping for air. A child in a distant playground moves gracefully propelling the swing to new heights. A crystal glass shatters with the precision of an operatic singer's voice. The Earth, the child, and the soprano play with oscillations. Not content with the simple vibrations of sound, or a mass on a string, or a screen door swinging to and fro, this active cast of characters forces...  [view full summary] A low rumble through the Earth convulses a highway like a fish gasping for air. A child in a distant playground moves gracefully propelling the swing to new heights. A crystal glass shatters with the precision of an operatic singer's voice. The Earth, the child, and the soprano play with oscillations. Not content with the simple vibrations of sound, or a mass on a string, or a screen door swinging to and fro, this active cast of characters forces the systems and produces fascinating results. To understand what is happening, this chapter reviews the simplest vibrating system before exploring the more complex activities of the players. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

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Split image By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School A converging lens bends all rays of light parallel to the principal axis (the axis of symmetry of the lens) in such a way that they converge at a single point referred to as the focus. The lens also takes the light emerging from one point and focuses that light to a point on the other side of the lens. This then provides the surprising and technologically vital property of image formation in lenses. In this chapter, a broken lens is used to find...  [view full summary] A converging lens bends all rays of light parallel to the principal axis (the axis of symmetry of the lens) in such a way that they converge at a single point referred to as the focus. The lens also takes the light emerging from one point and focuses that light to a point on the other side of the lens. This then provides the surprising and technologically vital property of image formation in lenses. In this chapter, a broken lens is used to find a description of the resulting light pattern. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49

Book Chapter

Gravitational redshift By: Arthur Eisenkraft and Larry D. Kirkpatrick Grade Level: High School Edwin Hubble showed that most stars (and galaxies) are receding from Earth. Because of the expansion, the frequencies of the spectral lines from the stars are shifted to lower values—that is, the light is redshifted. However, this is not the only redshift that occurs. A photon leaving a star is also redshifted as it rises in the gravitational field of the star. The gravitational redshift for our sun is too small to be detected accurately, but the...  [view full summary] Edwin Hubble showed that most stars (and galaxies) are receding from Earth. Because of the expansion, the frequencies of the spectral lines from the stars are shifted to lower values—that is, the light is redshifted. However, this is not the only redshift that occurs. A photon leaving a star is also redshifted as it rises in the gravitational field of the star. The gravitational redshift for our sun is too small to be detected accurately, but the redshifts of photons leaving white dwarfs can be measured and are equivalent to the redshifts. This chapter presents a combination of the effects of these two types of redshift. [hide full abstract] Member Price: $2.79      Nonmember Price: $3.49