1. physics

    Jessica weighs 540 Newtons, According to Newton's 3rd law, if the Earth pulls on Jessica 540 N, then Jessica pulls on the Earth 540 N acting in the opposite direction. If she trips while rollerblading, why will she fall to the ground
  2. main ideas study unit

    scientist generally agree that earth is getting warmer due to what call the green house effectt. a greenhouse used for plant stay warm because sunlightand heat come through the glass roof are mostly trapped by the grass something like that happen on earth.
  3. physics

    i posted this earlier but am now stuck on getting through the algebra 1. The problem statement, all variables and given/known data 13) (II) At what distance from the Earth will a spacecraft on the way to the Moon experiance zero net force due to these two
  4. science

    Granite is an igneous rock that forms from magma cooled below Earth's surface.Why would granite have larger crystals than igneous rocks formed from lava cooled above Earth's surface?
  5. Chemistry

    It is estimated that uranium is relatively common in the earth’s crust, occurring in amounts of 4 g/metric ton. A metric ton is 1000 kg. At this concentration, what mass of uranium is present in 1.0 mg of the earth’s crust?
  6. physics

    Calculate the angular momentum of the Earth the arises from its spinning on its axis. Also calculate the angular momentum of the Earth that arises from its orbital motion around the sun. Please help I'm stumped on a take home test.
  7. Earth Science

    what is the driving force for the movement of the lithospheric plates? a- heat from the sun b- unequal distribution of heat within Earth c- heat in the atmosphere d- unequal distribution of heat from the oceans My answer is B
  8. Physics

    1. Planet X orbits the sun with a mean orbital radius that is 6200 times that of earth. Its diameter is twice that of earth, and its mass is 8 times that of earth. A) Calculate the year of the planet X. B) Calculate the acceleration due to gravity on
  9. Physics

    On a distant planet, golf is just as popular as it is on earth. A golfer tees off and drives the ball 4.3 times as far as he would have on earth, given the same initial velocities on both planets. The ball is launched at a speed of 40 m/s at an angle of
  10. physics (Newton"s law of gravitation)

    Could anyone please help me with this problem? I would really appreciate it. The top of Mt. Everest is 8850 m above sea level. Assume that sea level is at the average Earth radius of 6.38×106 m. What is the magnitude of the gravitational acceleration at
  11. science

    The moon spins,or_____ ,in space. The words to use for this is revolves ...rotates...orbit lunar eclipse...or solar eclipse
  12. physics

    Europa is one of Jupiter's moons. This moon is in a circular orbit of 6.71x10^8 meters within a period of 3.55 days. What is the mass of Jupiter?
  13. physics

    Europa is one of Jupiter's moons. This moon is in a circular orbit of 6.71x10^8 meters within a period of 3.55 days. What is the mass of Jupiter?
  14. Physics

    A 3.2 cm diameter plastic sphere is charged to -19.0 nC. What orbital frequency must a proton have to maintain a circular orbit around the sphere 2.4 mm above its surface?
  15. Chemistry

    If the wavelength of an electron is equal to the radius of the n=2 orbit in He+, what must the velocity of the electron be? The answer is 6.88 x 10^6 m/s How do I find this? I tried E = Z^2hcRh/n^2 and E= 1/2mv^2 with Z = 1, n=2, m=9.109E-31
  16. science

    I remember hearing something about how the Mayans predicted that it took so many days for the sun to orbit the sun and then Nasa recently figure out that they were only slightly off. Does anyone know about this? Thanks
  17. physics (Mathmate)

    The space shuttle is in a 250 mile high orbit. What are the shuttle's orbital period, in minutes and its speed?
  18. Physics

    The mass of a certain planet is six times the mass of the earth and the diameter of the planet is twice the diameter of the earth. Find the acceleration od gravity on the surface of this planet. HELP ME SOLVE! THANKS!
  19. science help PLS

    An astronomer see a star that is very far away but still very bright. What can she conclude about the star? The star must be very large. The star must be very small. The star must be moving away from Earth. The star must be moving closer to Earth.
  20. Science

    Describe Earth's rotation in terms of its axis and length of time to rotate. The earth's axis slowly changes in the way it points. It changes direction over time. One effect of this precession, is the changing position of the North Celestial Pole. It takes
  21. science

    During space flight, astronauts often refer to forces as multiples of the force of gravity on Earth's surface. What does a force of 5g mean to an astronaut? If Earth were twice as massive but remained the same size, what would happen to the value of g?
  22. physics

    The radius of a planet R1 and satellite revolves round it in a circle of radius R2. The time period of revolution is T.find the acceleration due to the gravitation of the planet at its surface.
  23. Physics: fictitious forces

    A plumb bob does not hang exactly along a line directed to the center of the Earth's rotation. How much does the plumb bob deviate from a radial line at 39.0° north latitude? Assume that the Earth is spherical. This was in my textbook with an angle of 35
  24. Earth's Dynamic Atmosphere

    Air pressure doesn't crush everything underneath it because A. air pressure is hypothetical and not a real force. B. air pressure is strong enough. C. things on earth have learned to withstand the constant pressure. D. air pressure is exerted in all
  25. Math

    Today Star Satellite is offering the following special package to new customers: a one-time set-up fee of $10, the first month for free, and $32 per month thereafter. Which equation best represents k, the total cost of service for m months? A k = (10 +
  26. Physics-mechanics

    Find the speed and period of a satellite that orbits Mars 175 km above it's surface. (The average radius of Mars is 3.40 x 10^6; and it's mass is 6.42 x 10^23. Use all necessary formulas and show all clear-working, to enable me understand how you arrived
  27. Physics-mechanics

    Find the speed and period of a satellite that orbits Mars 175 km above it's surface. (The average radius of Mars is 3.40 x 10^6; and it's mass is 6.42 x 10^23. Use all necessary formulas and show all clear-working, to enable me understand how you arrived
  28. physics

    Suppose that 7.40 g of hydrogen is separated into electrons and protons. Suppose also that the protons are placed at the Earth's north pole and the electrons are placed at the south pole. What is the resulting compressional force on the Earth?
  29. Physical Science

    The acceleration due to gravity is about 10 m/s2 at the Earth's surface. What is the acceleration due to gravity for a person on the space station orbiting 200 miles above the Earth's surface?
  30. Math

    The ocean covers about 71% of the Earth's surface. If the total surface area of the Earth is about 510 million square kilometers, how many square kilometers are covered by the ocean? 362.10
  31. physics

    how does the gravitational force exerted by earth on the sun compare with the gravitational force exerted by sun on the earth? and would you expect tides to be higher at the equator or at the north pole? why?
  32. Reading skills

    According to science, the fastest speed possible for anything is the speed of light. The speed of light is about 186,000 miles per second. That means that in one minute, light travels 11,160,000 miles. The star nearest Earth is the Sun. It's about
  33. Chemistry

    How many moles of ozone does the atmosphere hold? For a sense of scale,compare the amount to the total carbon dioxide emitted annually from fossil fuel burning, cement production and deforestation (7900 Tg/C). Given with the facts the amount of ozone is
  34. reading

    According to science, the fastest speed possible for anything is the speed of light. The speed of light is about 186,000 miles per second. That means that in one minute, light travels 11,160,000 miles. The star nearest Earth is the Sun. It's about
  35. physics

    The polar ice caps contain about 2.76E+19 kg of ice. This mass contributes negligibly to the moment of inertia of Earth because it is located at the poles, close to the axis of rotation. Estimate the change in the length of the day that would be expected
  36. science

    Which statement best describes Newton’s Law of Universal Gravitation? A.Large objects, like Earth and the Sun, attract other objects everywhere in the universe. B.Gravity is a kind of magnetic force between objects and Earth. C.Gravity is the result of
  37. physics please help

    An astronaut stands at a position on the Moon such that Earth is directly overhead and releases a Moon rock that was in her hand. (c) What is the gravitational force exerted by the Earth on the same 2.7-kg rock resting on the surface of the Moon? answer in
  38. math

    1. Many people know that the weight of an object varies on different planets, but did you know that the weight of an object on earth also varies according to the elevation of the object? In particular, the weight of an object follows this equation: , where
  39. Physics

    In an attempt to reduce the extraordinarily long travel times for voyaging to distant stars, some people have suggested traveling at close to the speed of light. Suppose you wish to visit a star which is 410 ly away, and that you want your 24000 kg rocket
  40. physics

    During an Apollo lunar landing mission, the command module continued to orbit the Moon at an altitude of about 58.6 km. How long did it take to go around the Moon once, in seconds?
  41. Physics

    A proton orbits a negatively charged wire that has a linear charge density of 8.0 x 10 -9 C/m. What speed must the proton have to maintain a circular orbit at 1.3 cm?
  42. physics

    During an Apollo lunar landing mission, the command module continued to orbit the Moon at an altitude of about 113 km. How long did it take to go around the Moon once?
  43. physics

    During an Apollo lunar landing mission, the command module continued to orbit the Moon at an altitude of about 165 km. How long did it take to go around the Moon once?
  44. Physics

    A single electron orbits a lithium nucleus that contains three protons (+3e). The radius of the orbit is 1.76*10^-11m. Determine the kinetic energy of the electron.
  45. Physics

    Hello recently I was asked to find the time it takes a satalite that is geocentric (that always stays above the same exact spot of the earth) so... I was given the radius of 61 earth radius or simply 3.89 E 6 m mass of earth what G equals and have to use
  46. Science (Physics)

    Gravity on the surface of the moon is only 1 6 as strong as gravity on the Earth. What is the weight of a 30 kg object on the Earth? The acceleration of gravity is 10 m/s 2 . Answer in units of N What is the weight on the moon? Answer in units of N What is
  47. s

    According to science, the fastest speed possible for anything is the speed of light. The speed of light is about 186,000 miles per second. That means that in one minute, light travels 11,160,000 miles. The star nearest Earth is the Sun. It's about
  48. Physics wavelength problem! Please Help!

    A communications satellite transmits a radio wave at a frequency of 5 • 109 Hz. What is the signal’s wavelength? Assume the wave travels in a vacuum. Show your work Thank You!
  49. science help PLS

    Which of the following correctly describes a way in which Earth’s atmosphere interacts with the geosphere? It contains gases that living organisms breathe. It contains gases that trap incoming solar radiation. It provides a medium for cycles that provide
  50. Math Grade 12

    So the question is basically asking which mountains peaks can be seen from Oahu. Island Distance(Mi) Mountain Height(ft) Lanai - 65 - Lanaihale - 3,370 Maui - 110 - Haleakala - 10,023 Hawaii - 190 - Mauna Kea - 13,796 Molokai - 40 - Kamakou - 4,961 A)
  51. math

    The ratio of an objects weight on earth to its weight on Neptune is 5:7. How much would a person who weighs 150 pounds on earth weigh on Neptune? A.210 pounds B.750 pounds c.107 1/7 pounds D.170 pounds
  52. Astronomy

    Only one side of the moon is visible from Earth because... A. the moon does not rotate on its axis. B. the moon does not revolve around Earth. C. the moon rotates faster than it revolves. D. the moon revolves once and rotates once in the same period of
  53. Physics

    (c) On Earth a fit astronaut without a space suit and life support pack can leap straight up and leave the ground with an initial vertical velocity of about v1y = 2.4 m/s and rise to a height of about h = 0.24 m above the point where he first loses contact
  54. Physics

    On Earth a fit astronaut without a space suit and life support pack can leap straight up and leave the ground with an initial vertical velocity of about v1y = 2.4 m/s and rise to a height of about h = 0.24 m above the point where he first loses contact
  55. Check my answers?

    A. 75 % B. 12.5% C. 25% D. 3.13% E. 9.38% 3. what percentage of land on the earths surface is inhospital lands? - B 4. what percentage of earths surface is covered by land? - C 5. what percentage of land on earth is usable, for living on, but not for
  56. re math

    Many people know that the weight of an objectvaries on different planets,butdid you know that the wieght of an object on earth also varies according to the elevation oj an object.in particualr ,the weight of an equation follows this equation:w=cr -2
  57. Ethics

    1. Hill claims that a fruitful way to think about the badness of destroying the environment is? To think about what kind of human would choose to destroy the earth. To appeal to theories about God and care for the earth. To examine people’s intuitions
  58. physics

    The sun’s mass is about 2.7 x 107 times greater than the moon’s mass. The sun is about 400 times farther from Earth than the moon. How does the gravitational force exerted on Earth by the sun compare with the gravitational force exerted on Earth by the
  59. Physics

    A proton moves eastward in the plane of Earth’s magnetic equator so that its distance from the ground remains constant. What is the speed of the proton if Earth’s magnetic field points north and has a magnitude of 5.2 × 10−5 T? The acceleration
  60. Science

    Which of the rock-forming mineral groups makes up the largest group of minerals in the Earth's crust? Look here for your answer. http://www.google.com/search?hl=en&lr=&ie=ISO-8859-1&q=minerals+earth%27s+crust&btnG=Search
  61. spanish

    help me translate please!! i tried it myself but it was a mess! :( My name is Isabella and I am 14 years old. I live with my parents and two brothers in the outskirts of Newport. My school is a few miles away from where I live, I go to school by coach but
  62. Science 2

    One light year is about 9 trillion kilometers. Arcturus is a star that is 37 light years from earth. If you are about 11 years old now , how old will you be when light that is leaving. Arcturus today reaches Earth ? How far, in kilometers, will it have
  63. phys

    An astronaut drops an object from rest (relative to the planet) on a planet alpha (having the same radius as of earth) from an altitude of one radius above the surface. When the object hits the surface its speed is 3.98 times what it would be if the same
  64. math

    The scale for an earth model is 1:40000000. The diameter of the earth is 12,756.32km. a)What is the diameter of the model in cm? I got 31.9cm (just need help on part b!) b) If the model is cut in half, how many jars of paint would be needed to paint each
  65. Physics

    What provides the centripetal force : i)on the elctron orbiting the proton in a hydrogen atom ii)satellite orbiting the planet iii)on the child being whirled round in a chair on the end of a chain in the fairground ride ? Ayuada por favorr :)
  66. Math

    Can you help me solve this problem? Cuz i cant seem to figure it out. An orbiting satellite traveled 3,225 miles in 40 minutes. Find its speed in miles per hour. (Round your answer to the next whole number.) (a)103 (b)4,838 (c)4,267 (d)6,200 (e)150
  67. math

    An object weighing 5 pounds on Earth will weigh 2 pounds on Mercury. The Brooklyn Bridge weighs 14,695 tons on Earth. What would it weigh on Mercury (in tons) ?
  68. math

    The ocean covers about 71% of the Earth’s surface. If the total surface area of the Earth is about 510 million square kilometers, how many square kilometers are covered by the ocean?
  69. astonomy

    Assume that earth and mars are perfect spheres with the radii of 6,371km and 3,390 km, respectively. Calculate the surface area of earth. b)calculate surface area of mars
  70. Science Physics

    An object weighs 12 N on earth. When it is brought to Mars, it has a weight of 4.8 N. What is the acceleration due to gravity on Mars? (Taking the acceleration due to gravity on earth is 10 m/s²)
  71. Physics

    Please help..... When something is thrown over a large distance (on earth ) what new factor comes into play? 1- The decrease in gravity over long distance 2- The increase in gravity over long distance 3- The tendency of thrown objects to fall to the ground
  72. Physics

    In order for a satellite in free fall to maintain uniform circular motion, ______________. a) there must be a tangential acceleration b) there must be angular acceleration c)there must be a centripetal force d) there must be a circumventing force Its
  73. Physics

    The equation describing the (r, \theta ) coordinates of points along a single field line of a magnetic dipole is r=R_0 \sin ^2(\theta ) where \theta =0 is in the direction of the dipole moment and R_0 is a constant which is different for each field line.
  74. science

    Earth titled axis affects the strength of sunlight in different places of earth's surface. If you are in an area that receiving less direct sunlight,where are you located? a) near the equator b) near the north pole c) near the south pole d) near the north
  75. physics

    If Earth's mass were suddenly and magically reduced to half its present value, the Sun's gravitational force on Earth would A. be reduced by a factor of 2. B. be reduced by a factor of 4. C. increase by a factor of 2. D. remain the same. I was told it
  76. Physics

    A spaceship lifts off from the Earth with constant acceleration. 9 seconds into the flight, a small piece of the ship breaks off and falls back to the Earth. If the piece hit the ground 11.5 seconds after breaking off from the spaceship, what is the
  77. science

    Earth titled axis affects the strength of sunlight in different places of earth's surface. If you are in an area that receiving less direct sunlight,where are you located? a) near the equator b) near the north pole c) near the south pole d) near the north
  78. physics

    An airplane has a velocity of 400 km/h relative to the wind. At the same time, a wind blows northward with a speed of 75 km/h relative to earth. Find the direction that the airplane must head in order to move in an easterly direction relative to earth.
  79. physics

    At a certain location on the Earth, the horizontal component of the Earth’s magnetic field is 2.5 ·10−5 T due North. A proton moves eastward with just the right speed for the magnetic force on it to balance its weight so the net force on the
  80. Physics

    Suppose an electron was bound to a proton as in the hydrogen atom, but by the gravitational force rather than by the electric force. What would be the radius and energy of the first Bohr orbit?
  81. Physics

    In a binary star system, two stars orbit about their common center of mass, as shown in the figure . If r2 = 2r1, what is the ratio of the masses m2/m1 of the two stars?
  82. 8th grade science

    explain that gravitational force is the dominant force determining motions in the solar system and in particular keeps the planets in orbit around the sun
  83. PHYSICS

    In the Bohr model of the hydrogen atom, the electron makes 6.00×10^15 rev/sec around the nucleus.What is the average current at a point on the orbit of the electron?
  84. Astronomy

    If a space probe were sent into orbit around the sun that brought it as close as 0.5 AU to the sun and as far away as 5.5 AU, what would its orbital period be? Can I use Kepler's 3rd law for this? I'm not sure how to take into account both AUs...
  85. physics

    Assume you are agile enough to run across a horizontal surface at 8.10 m/s on an airless spherical asteroid of uniform density 1.9x103 kg/m3, independently of the value of the gravitational field. To launch yourself into orbit by running, what would be (a)
  86. physics

    Assume you are agile enough to run across a horizontal surface at 8.10 m/s on an airless spherical asteroid of uniform density 1.9x103 kg/m3, independently of the value of the gravitational field. To launch yourself into orbit by running, what would be (a)
  87. science

    . How does the principle of uniformitarianism accounts for occasional catastrophic events such as meteorite impacts, huge volcanic eruptions, or great earthquakes? In what ways do geologic processes affect a person's daily life? . When astronauts brought
  88. Physics

    When astronomers find a redshifted celestial object, they say that the object is moving away from Earth. Can the redshift be interpreted as the Earth moving away from the celestial object?
  89. math

    An object that weighs about 2.1 pounds on the moon weighed 12.56 pounds on Earth. About how much would an astronaut who weighs 174 pounds on Earth weigh on the moon?
  90. earth

    how long does it take for light from Jupiter to come to earth. for example tonight the planet Jupiter can be seen by the moon, 2/25/12 and we see the light from the planet and how old is that light. thanks. jerry in colorado USA
  91. msth

    the mass of earth is 5.97*10^24 kilograms the mass of the moon is 7.34 *^22 kilograms what is the combines mass of earth ad the moon. express your answer in scientific notation
  92. physics

    At the surface of Mars, the acceleration due to gravity is 3.72 m/s^2. A watermelon has a mass of 4.5 kg here on Earth. a) What is its weight here on earth? b) What is its mass in Mars? c)What is its weight in Mars?
  93. Physics

    A rock is falling towards the Earth. Suppose the action force is the pull of the Earth on the rock. What is the reaction force? I do not know how to find the reaction force.
  94. science

    Hi...I am having trouble on one last science question. Which statement supports the fact that Earth rotates about its axis from West to East? a. only one face of the moon is visible from earth b. the moon's phases change every day over the course of 29
  95. Physics

    A car travels due east with a speed of 50.0 km/h. Raindrops are falling at a constant speed vertically with respect to the Earth.The traces of the rain on the windows of the car make an angle of 60 degrees with the vertical. Find the velocity of the rain
  96. Physics

    Which of the following involves a non-zero net force? I. A hockey-puck sliding at a constant speed on ice. II. The earth revolving around the sun at a constant speed. III. An object falling near the surface of the earth. A) I only B) III only C) Both I and
  97. Physics 1

    Find the ratio of your weight on the Earth to your weight on the surface of the Earth's Moon. WEarth/WEarth's Moon=
  98. Physics 1

    Find the ratio of your weight on the Earth to your weight on the surface of the Earth's Moon. WEarth/WEarth's Moon=
  99. physics

    the gravity that sun has on the moon is about 2 times more than the gravity from earth so why doesn't moon run away from earth to sun?
  100. science

    The mass of the girl in earth is 24kg. What is her mass and weight in moon if the moon's gravity is 1/6 of the earth' gravity?