review and synthesis: chapters 1–5
... from the star with mass M1. 17. Strategy and Solution Consider a cord attached to a wall at one end and pulled by one of the boys at the other end. The cord does not accelerate when the boy pulls it; thus, the force on the cord from the wall must be equal in magnitude to the pulling force. This situ ...
... from the star with mass M1. 17. Strategy and Solution Consider a cord attached to a wall at one end and pulled by one of the boys at the other end. The cord does not accelerate when the boy pulls it; thus, the force on the cord from the wall must be equal in magnitude to the pulling force. This situ ...
30155-doc - Project Gutenberg
... the footpath notices that the stone falls to earth in a parabolic curve. I now ask: Do the "positions" traversed by the stone lie "in reality" on a straight line or on a parabola? Moreover, what is meant here by motion "in space"? From the considerations of the previous section the answer is self-ev ...
... the footpath notices that the stone falls to earth in a parabolic curve. I now ask: Do the "positions" traversed by the stone lie "in reality" on a straight line or on a parabola? Moreover, what is meant here by motion "in space"? From the considerations of the previous section the answer is self-ev ...
in search of antimatter in the universe
... Spiral galaxies do not often feature AGN, and so instead, we consider elliptical galaxies, which have stars evenly distributed throughout the volume of an ellipse. One such galaxy is Centaurus A, which is the closest galaxy to us with an AGN jet, at 3.7 Mega parsecs (1 parsec is 3.1x1016 m). This me ...
... Spiral galaxies do not often feature AGN, and so instead, we consider elliptical galaxies, which have stars evenly distributed throughout the volume of an ellipse. One such galaxy is Centaurus A, which is the closest galaxy to us with an AGN jet, at 3.7 Mega parsecs (1 parsec is 3.1x1016 m). This me ...
Building galaxies Hunt, Leslie Kipp
... plates, the Hubble sequence is in fact a physical one. Several quantifiable parameters vary significantly with Hubble type. Already from photographic material it was known that optical colors (U −B, B −V ) and surface brightness depend on morphological type with later type spirals tending to have fa ...
... plates, the Hubble sequence is in fact a physical one. Several quantifiable parameters vary significantly with Hubble type. Already from photographic material it was known that optical colors (U −B, B −V ) and surface brightness depend on morphological type with later type spirals tending to have fa ...
Document
... Tensions are equal (“ideal” pulley, light rope) Accelerations are equal in magnitude (why?), opposite in ...
... Tensions are equal (“ideal” pulley, light rope) Accelerations are equal in magnitude (why?), opposite in ...
Slide 1
... Answer: Two kilograms of anything has twice the inertia and twice the mass of one kilogram of anything else. In the same location, where mass and weight are proportional, two kilograms of anything will weigh twice as much as one kilogram of anything. Except for volume, the answer to all the question ...
... Answer: Two kilograms of anything has twice the inertia and twice the mass of one kilogram of anything else. In the same location, where mass and weight are proportional, two kilograms of anything will weigh twice as much as one kilogram of anything. Except for volume, the answer to all the question ...
Chapter2 Laws of Motion
... together changes in response to the total force acting on the object, including gravity ...
... together changes in response to the total force acting on the object, including gravity ...
Chapter 11 Gravity ∑
... During a trip back from the moon, the Apollo spacecraft fires its rockets to leave its lunar orbit. Then it coasts back to Earth where it enters the atmosphere at high speed, survives a blazing re-entry and parachutes safely into the ocean. In what direction do you fire the rockets to initiate this ...
... During a trip back from the moon, the Apollo spacecraft fires its rockets to leave its lunar orbit. Then it coasts back to Earth where it enters the atmosphere at high speed, survives a blazing re-entry and parachutes safely into the ocean. In what direction do you fire the rockets to initiate this ...
General Astrophysics And Comparative Planetology
... Earth-sized based only on visual observations and an assumed surface reflectance. This estimate was reduced when Pluto’s icy nature was guessed. Finally the Charon-Pluto eclipses during the late 1980s constrained Pluto’s radius to be much smaller—0.18 Earth radii. Sedna is a recently discovered smal ...
... Earth-sized based only on visual observations and an assumed surface reflectance. This estimate was reduced when Pluto’s icy nature was guessed. Finally the Charon-Pluto eclipses during the late 1980s constrained Pluto’s radius to be much smaller—0.18 Earth radii. Sedna is a recently discovered smal ...
Kinematics
... exercise we will face with vectors is the combination of two different vectors of the same type (i.e., two different velocities). This is a very simple exercise when the two vectors point in the exact same (or exact opposite) direction; it is often challenging to try and combine two similar vectors ...
... exercise we will face with vectors is the combination of two different vectors of the same type (i.e., two different velocities). This is a very simple exercise when the two vectors point in the exact same (or exact opposite) direction; it is often challenging to try and combine two similar vectors ...
and invariance principles Events, laws of nature,
... granted. In fact, it may be argued that laws of nature could not have been recognized if they did not satisfy some elementary invariance principles such as those of Categories (a) and (b) - if they changed from place to place, or if they were also different at different times. The principle (c) is n ...
... granted. In fact, it may be argued that laws of nature could not have been recognized if they did not satisfy some elementary invariance principles such as those of Categories (a) and (b) - if they changed from place to place, or if they were also different at different times. The principle (c) is n ...
Measuring distances to the edge of the local group
... Scientific Justification Be sure to include overall significance to astronomy. For standard proposals limit text to one page with figures, captions and references on no more than two additional pages. We propose to measure the distance to the nearby dwarf irregular galaxies Sextans A, B, and NGC 310 ...
... Scientific Justification Be sure to include overall significance to astronomy. For standard proposals limit text to one page with figures, captions and references on no more than two additional pages. We propose to measure the distance to the nearby dwarf irregular galaxies Sextans A, B, and NGC 310 ...
Modified Newtonian dynamics
In physics, modified Newtonian dynamics (MOND) is a theory that proposes a modification of Newton's laws to account for observed properties of galaxies. Created in 1983 by Israeli physicist Mordehai Milgrom, the theory's original motivation was to explain the fact that the velocities of stars in galaxies were observed to be larger than expected based on Newtonian mechanics. Milgrom noted that this discrepancy could be resolved if the gravitational force experienced by a star in the outer regions of a galaxy was proportional to the square of its centripetal acceleration (as opposed to the centripetal acceleration itself, as in Newton's Second Law), or alternatively if gravitational force came to vary inversely with radius (as opposed to the inverse square of the radius, as in Newton's Law of Gravity). In MOND, violation of Newton's Laws occurs at extremely small accelerations, characteristic of galaxies yet far below anything typically encountered in the Solar System or on Earth.MOND is an example of a class of theories known as modified gravity, and is an alternative to the hypothesis that the dynamics of galaxies are determined by massive, invisible dark matter halos. Since Milgrom's original proposal, MOND has successfully predicted a variety of galactic phenomena that are difficult to understand from a dark matter perspective. However, MOND and its generalisations do not adequately account for observed properties of galaxy clusters, and no satisfactory cosmological model has been constructed from the theory.