1. Algebra 1

    Earth has a radius of about 6.4 x 10 to the 6th power m. Approximate the surface area of earth using the formula for the surface area is a sphere, S = 4 pi r squared. Earths surface is about 70 percent water. About how many square meters of earths surface
  2. Earth Science

    1. The water cycle is the _____. A. distribution of drinking water on Earth ?**? B. unending circulation of Earth's water supply ?**? C. the recycling of water after industrial use ?**? D. the evaporation of water from Earth's surface ?**? 2. Plants
  3. physics

    Assuming that 68.1% of the Earth's surface is covered with water at average depth of 1.21 mi. ,estimate the mass of the water on Earth. One mile is 1.609 km and the radius of the earth is 6.37 x 10^6 m. Answer in units of kg
  4. science

    Meteorites can make large depressions on Earth’s surface when they make impact. Why are so few of these depressions visible on Earth’s surface? • Earth is constantly changing it’s topography due to volcanic activity, or processes such as
  5. Science

    Where is most of the surface water on earth found? a) as freshwater in rivers b) as frozen water near the pole c) as groundwater under the surface d) as salt water in oceans I think its either A or D. Am I correct?
  6. Physics

    What is the Earth's gravitational force on you when you are standing on the Earth and when you are riding in the Space Shuttle 380 km above the Earth's surface? Answer as a fraction of the surface gravity of Earth. (The Earth's radius is 6400 km.)
  7. Ms.Sue August or Anonymous

    All 3 of you I see usually answer a lot of questions. Can you help me with some of these? 1. Erosion is a slow process that causes change to Earth's surface. All of the following are sources of erosion except A.wind B.earthquakes C.glaciers D.ocean waves
  8. physics problem!!

    If the water molecules in 5.70 g of water (H2O) were distributed uniformly over the surface of the Earth, how many such molecules would there be on 1.40 cm2 of the Earth's surface? -Molar mass Hydrogen gas(H2)=2.02 g/mol -Molar mass Oxygen gas (O2) = 32.0
  9. earth science

    The global ocean covers about 70% of the Earth’s surface. If all the ocean water was uniformly distributed over the whole surface, what would be its depth? Assume that the Earth is a perfect sphere, and the average ocean depth is 4 km.
  10. science

    Large craters are visible on the moon but not common on the earth's surface. Which of the following is the beady explanation of why large craters are not evident in the earth's surface in photos taken from space. A.three quarters of the earth's surface is
  11. calculus

    the weight of a person on or above the surface of the earth varies inversely as the square of the distance the person is from the center of the earth. if a person weighs 180 pounds on the surface of the earth and the radius of the earth is 3900 miles, what
  12. Algebra 1

    There is three times as much water as land on Earth's surface. What percent of earth is covered by water?
  13. Environmental Science

    Earth's surface water is found in a.lakes b.rivers c.streams d.all of the above I picked d. because that's where SURFACE water is at right? yup ditto.....
  14. Science

    Which statement correctly describes the sun and earth? a. the sun and earth both have water. b. the sun and earth both have a surface called the crust. c. the sun and earth both have an atmosphere d. the sun and earth both have breathable air
  15. Physics

    Calculate the force of gravity on a spacecraft 19200 km (3 earth radii) above the Earth's surface if its mass is 1600 kg. Hint: At three earth radii from the surface of the Earth, the gravity force (weight) of the spacecraft will be reduced to (1/4)^2 =
  16. oceanography

    1. How much of the total water at earth's surface is fresh water? 2. Of all the freshwater at the earth's surface, what percent is found as ice and glaciers? 3. What percent of all freshwater is groundwater? 4. What percent of the rainfall that falls on
  17. Physics

    A projectile is fired vertically from Earth's surface with an initial speed v0. Neglecting air drag, how far above the surface of Earth will it go? (Use any variable or symbol stated above along with the following as necessary: ME for the mass of the
  18. biology

    What is the source of energy driving the hydrolic cycle? a. evaporation of the ocean water b. heat conducted from the earth's core to the surface c. radiant heat from the sun d. air currents returning to the earth's surface
  19. earth

    A particle weighs 120 N on the surface of the earth. At what height above the earth's surface will its weight be 30 N? Radius of the earth = 6,400 km.
  20. Science

    1) How does water vapour change into solid and liquid water above earth's surface? 2)does all surface runoff move directley into lakes, rivers and oceans? Please help asap it means alot!
  21. Physics

    Let us assume that the muon production happens at an altitude of about 15 kilometers above the surface of the Earth, and that the produced muons have a velocity of 0.99 c. Thus, in the Earth system, it takes the muon approx. 50500 nanoseconds to reach the
  22. science

    1.why is freshwater a limited resource? a)because most water on earth is in lakes** b)because most water on earth is in clouds c)because most water on earth is in the ground d)because most water on earth is salt water
  23. physic

    A satellite used in a cellular telephone network has a mass of 2010kg and is in a circular orbit at a height of 770km above the surface of the earthTake the gravitational constant to be G = 6.67×10−11N⋅m2/kg2 , the mass of the earth to be me =
  24. earth

    a space traveller determines the radius of a planet to be half of earth . After landing on its surface , he finds the acceleration due to gravity to be twice of that of surface of earth. Find the ratio of mass of planet to the earth
  25. physics

    Assuming the Earth's magnetic field averages about 0.50×10−4 T near Earth's surface, estimate the total energy stored in this field in the first 15km above Earth's surface. The radius of Earth is 6380 km.
  26. Physics

    Determine the ratio of Earth's gravitational force exerted on an 80-kg person when at Earth's surface and when 1000km above Earth's surface. The radius of Earth is 6370 km. I have tried (6370)^2/(7370)^2 = 0.747 and it is wrong??
  27. Science

    Why is freshwater a limited resource? A. because most water on Earth is in lakes B. because most water on Earth is in clouds C. because most water on Earth is in the ground D. because most water on Earth is saltwater D
  28. physics

    A satellite has a mass of 100 kg and is in an orbit at 2.00*10^6 m above the surface of the Earth (a) what is the potential enegry of the satellite at this location?(b) what is the magnitude of the gavitational forece on the satellite? a) Since the weight
  29. physics/math

    Calculate the magnitude of the gravitational force between the Earth and an m = 6.00 kg mass on the surface of the Earth. The distance to the center of the Earth from the surface is 6.37×103 km and the mass of the Earth is 5.98×1024 kg.
  30. Science

    1.)Why is Earth’s temperature just right for life? (1 point) A.)Earth’s core is hot enough to heat Earth’s surface. B.)Earth’s magnetic field creates suitable temperatures on Earth’s surface. C.)Earth’s crust is warmed by heat from the sun.
  31. chemistry

    Why is it possible to float a pin on the surface of water? A. The molecules of water on the surface change bonding as they dry out. B. The density of the pin is less than that of the water's surface. C. The surface tension of the water is so low. D. The
  32. Physical Science

    Many people mistakenly believe that the astronauts who orbit Earth are "above gravity." Earth's mass is 6×1024kg, and its radius is 6.38×106m (6380 km). Use the inverse-square law to find a height above Earth's surface at that the force of gravity on a
  33. physics

    A rocket is launched vertically from Earth's surface with a velocity of 3.4 km/s. How high does it go: From Earth's centre? From Earth's surface? how can this be done without any time or force mentioned ??
  34. Physics

    Earth has a mass of 5.97x10^24kg and a radius of 6.38x10^6m. Find the wight of a 65.0kg person on the surface of the earth and 1000km above the surface of earth?
  35. physics- please help me!

    Earth turns on its axis approximately once every 24 hours. The radius of Earth is 6.38 X 10^6 m. a.) If some astronomical catastrophe suddenly brought Earth to a screeching halt (a physical impossibility as far as we know), with what speed would Earth's
  36. biology

    What is the source of energy driving the hydrolic cycle? a. evaporation of the ocean water b. heat conducted from the earth's core to the surface c. radiant heat from the sun d. air currents returning to the earth's surface I chose a) evaporation of the
  37. Science

    Which of the following describes the slowest change on earth's surface? A) Gravity pulls an area of wet soil and rock downward in a landslide B) An earthquake releases energy that built up below Earth's surface C) Lava explodes from a volcano on an island
  38. Physics

    Many people mistakenly believe that astronauts who orbit the Earth are "above gravity." The mass of the Earth is 6x10 ^ 34 kg and radius is 6.38x10 ^ 6 m (6380 km) Use Newton's law to show that in the territory of the special ferry, 200 km above the
  39. science

    How much below the surface of the earth does the acceleration due to gravity become 1percent of its value at the earth surface? The earth is assume to be a sphere of radius 6.4×10^6m.
  40. algebra

    the weight of a body above the surface of earth varies inversely with the square of the distance from the center of the earth. if maria weighs 125 pounds when she is on the surface of the earth(3960 miles from the center),determine maria weight if she is
  41. algebra

    the weight of a body above the surface of earth varies inversely with the square of the distance from the center of the earth. if maria weighs 125 pounds when she is on the surface of the earth(3960 miles from the center),determine maria weight if she is
  42. Physics

    Calculate the percentage of Earth’s gravitational force on the ISS astronauts while orbiting at an altitude of 248 miles above Earth’s surface. To do this, compare the gravitational force on an orbiting astronaut to the force on the astronaut here at
  43. Science

    Can someone please please help me? I don't have a text book, i have a online book and it isn't working. Can someone please be nice and help me? Science isn't my subject! 1. Why is Earth’s temperature just right for life? (1 point) Earth’s core is hot
  44. Earth space science, check 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
  45. Physics

    At 6400 km above the earth’s surface, an object weighing 71 N on the surface would weigh only 18 N. Acceleration due to gravity will be about ¼ that on the surface of the earth.
  46. Physics

    The Earth is surrounded by an electric field on its surface that points toward the center of the Earth with an average magnitude of 150 N/C. If there is an electron that is released in vacuum at the Earth’s surface, what will the acceleration due to the
  47. 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
  48. phy

    (Q1)At what altitude above the earth's surface would the acceleration due to gravity be 4.9m/s-2?Assuming the mean radius of the earth is 64000000meters and the acceleration due to gravity 9.8m/s-2 on the surface of the earth
  49. physics

    Find the distance (measured in earth radii, RE) from the center of the earth to a point outside the earth where the acceleration of gravity due to the earth is exactly one ninth of its value on the surface of the earth.
  50. Physics

    A rocket starts from rest and moves upward from the surface of the earth. For the first 10s of its motion, the vertical acceleration of the rocket is given by a_y =( 2.70m/s^3)t, where the +y-direction is upward. 1) What is the height of the rocket above
  51. Physics

    When out in space in International Space Station (ISS), Astronauts experience weightlessness. The ISS’s orbit is 354 km (that is 3.54 x 105 m) above the surface of the earth (You can get more educational NASA resources from: The distance separating the
  52. Maths

    Assuming the earth to be a sphere of radius 6370 km.If seventy five percent of the earth's surface is covered by water, then find how many square kilometres is area of the land.
  53. math

    Assuming the earth to be a sphere of radius 6370km if seventy five percent of the earth's surface is covered by water then find how many square kilometres is area of the land
  54. physics

    How high does a rocket have to go above the Earth’s surface so that its weight is reduced to 33.7 % of its weight at the Earth’s surface? The radius of the Earth is 6380 km and the universal gravitational constant is 6.67 × 10 −11 N · m 2 /kg 2
  55. Physics

    At the heighest point on earth, the distance to the center of the earth is approximately equal to 1.0014 times the radius of the earth. What would be in N/kg the magnitude of the gravitational field (g) due to the earth at that position? Assume 9.8 N/kg
  56. earth

    What happens when a cold surface water current collides with a warm surface water current?
  57. Science

    An artificial satellite circles around the earth at the height where the gravitational force is one fourth of that at earth's surface. If the earth's radius is R the height of the satellite above the surface of the earth is?
  58. Physics

    The Earth is surrounded by an electric field on its surface that points toward the center of the Earth with an average magnitude of 150 N/C. If there is an electron that is released in vacuum at the Earth’s surface, what will the acceleration due to the
  59. Chemistry

    A. The molecules of water on the surface change bonding as they dry out. B. The density of the pin is less than that of the water's surface. C. The surface tension of the water is so low. D. The force exerted by the mass of the pin does not increase the
  60. Physics

    Given that the Earth's radius is 6.37x10^6 m and taking the earth's gravitational field at its surface to be 9.81N/kg, find the gravitational potential at the Earth's surface.
  61. Physics

    When the space shuttle (mass of the shuttle = 2 x10^6 kg) was at the outer limit of Earth's atmosphere (distance = 350 km above Earth's surface), astronauts measured the gravitational force from Earth to be equal to 1.7 x 10^7 newtons. Assuming that both
  62. physics

    As you walked on the moon, the earth’s gravity would still pull on you weakly and you would still have an earth weight. How large would that earth weight be, compared to your earth weight on the earth’s surface? (Note: The earth’s radius is 6378 km
  63. Chemistry

    The mass of the earth is known to be about 5.98 X10^24kg assume that it is approx. spherical with an average diameter of 1.276X10^7 METERS. from these data calculate the average density of the earth(g/cm^3) could the earth be made mostly of water
  64. jupiter and earth

    The planet of Jupiter is more than 300 times more massive than earth.however,an object scarcely weighs 3 times as much on the surface of Jupiter as it does on the surface of the earth. How can that be? Determine the radius of Jupiter in terms of earth
  65. Physics

    Suppose a new extrasolar planet is discovered. Its mass is double the mass of the Earth, but it has the same density and spherical shape as the Earth. How would the weight of an object at the new planet's surface differ from its weight on Earth? (Let Wnew
  66. Physics

    When out in space in International Space Station (ISS), Astronauts experience weightlessness. The ISS’s orbit is 354 km (that is 3.54 x 105 m) above the surface of the earth. The distance separating the center of the earth from the center of the ISS is
  67. phy 231

    It takes 23 hours 56 minutes and 4 seconds for the earth to make one revolution (mean sidereal day). a.What is the angular speed of the earth? I got 7.292x10^-5 rad/s b.Assume the earth is spherical. Relative to someone on the rotation axis, what is the
  68. PHYSICS

    THE MASS OF VENUS IS 81.5% OF THE EARTH AND ITS RADIUS IS 94.9% THAT OF THE EARTH. A)COMPUTE THE ACCELERATION DUE TO GRAVITY ON THE SURFACE OF VENUS FROM THESE DATA.B)IF A ROCK WEIGHS 75.0N ON EARTH,WHAT WOULD IT WEIGH ON THE SURFACE OF VENUS?
  69. physics

    Calculate the magnitude of the gravitational force between the Earth and an m = 6.00 kg mass on the surface of the Earth. The distance to the center of the Earth from the surface is 6.37×103 km and the mass of the Earth is 5.98×1024 kg. B)Calculate the
  70. science

    water from the earths surface moves in the air by ? and becomes ?. evaporation, and becomes water vapour in the earth's atmosphere
  71. Algebra II

    The force of attraction between the earth and some object is called the weight of that object. The law of gravitation states, then, that the weight of an object is inversely proportional to the square of its distance from the center of the earth. If a
  72. Algebra II

    The force of attraction between the earth and some object is called the weight of that object. The law of gravitation states, then, that the weight of an object is inversely proportional to the square of its distance from the center of the earth. If a
  73. Astro

    What is the distance in meters from the Earth's center to a point out-side the Earth where the gravitational acceleration due to the Earth is 1/20 of its value at the Earth's surface?
  74. colllege physics

    What is the distance from the Earth's center to a point outside the Earth where the gravitational acceleration due to the Earth is 1/45 of its value at the Earth's surface?
  75. Calculus

    A spacecraft is in an elliptical orbit around the earth. At the time t=0 hours, it is at its apogee (highest point), d=1000 km above the earth's surface. It is at its perigee (lowest point) d=100 km above the surface 50 minutes later. a. Assuming that d
  76. Math - Algebra

    If a man wewighs 41 newtons (N) on the surface of the earth while he weighs 81.5N on the surface of the moon, approximately how much lighter is he on the moon? What would be his weight on the surface of the earth if he weighs 90 N on the surface of the
  77. Physics

    a. 2 objects each of mass 200 kg and 500 kg are separated by 50 cm. Where body of mass 20 kg should be placed so that the resultant force of gravity experienced by objects equal to zero? b. launched a rocket leaving Earth. Known radius of the earth 6.4 x
  78. Physics

    What is the distance from the Earth's center to a point outside the Earth where the gravitational acceleration due to the Earth is 1/20 of its value at the Earth's surface?
  79. phy

    What is the distance from the Earth's center to a point outside the Earth where the gravitational acceleration due to the Earth is 1/12 of its value at the Earth's surface?
  80. physics

    What is the distance from the Earth's center to a point outside the Earth where the gravitational acceleration due to the Earth is 1/22 of its value at the Earth's surface? _ m
  81. physics

    What is the distance from the Earth's center to a point outside the Earth where the gravitational acceleration due to the Earth is 1/45 of its value at the Earth's surface?
  82. 465465

    A satellite is orbiting the earth just above its surface. The centripetal force making the satellite follow a circular trajectory is just its weight, so its centripetal acceleration is about 9.81 m/s2 (the acceleration due to gravity near the earth's
  83. Physics

    A satellite is orbiting the earth just above its surface. The centripetal force making the satellite follow a circular trajectory is just its weight, so its centripetal acceleration is about 9.81 m/s2 (the acceleration due to gravity near the earth's
  84. PHYSIC

    1)What must be the orbital speed of a satellite in a circular orbit 740 above the surface of the earth? 2)What is the period of revolution of a satellite with mass that orbits the earth in a circular path of radius 8000 (about 1630 above the surface of the
  85. algebra

    The force of gravity is inversely proportional to the square of the center of the earth. if you weigh 120 lbs on the surface of the earth, how much would you weigh 250 miles above the surface? (Earth's radius = 4000 miles)
  86. Science

    A Space Traveller determine the radius of a Planet to be half that of the earth after landing on its surface he find the acceleration due to gravity to be twice of the surface of the earth find the ratio of the mass of a planet to the earth
  87. Physics 2

    what magnetic force would an electron experience due to Earth’s magnetic field if it were moving at 3x10E6 m/s directly away from earth’s surface? (Earth’s B-field in the region is parallel to the surface and has a strength of 550 µT)
  88. Physics

    A 6.80 x 10^4 kg space shuttle moving at 7.90 x 10^4 m/s reenters the earth's atmosphere 80.0 km above the earth's surface. What is the shuttle's total mechanical energy with respect to earth's surface? I know the answer is E= 2.173 x 10^12J But I don't
  89. Physics

    When we say that the weight of an object is Mg, and that g = 9.8 N/kg, what assumptions are we making? Which of the below? -The distribution of mass in the earth is spherically symmetric. -The density of the earth is the same everywhere. -The earth's
  90. Physics

    When we say that the weight of an object is Mg, and that g = 9.8 N/kg, what assumptions are we making? Which of the below? The distribution of mass in the earth is spherically symmetric. The density of the earth is the same everywhere. The earth's interior
  91. physics

    9. The surface of the earth is approximately 6,400 km from its center. If the mass of the earth is 6.0 x 1024 kg, what is the acceleration due to gravity near the surface?
  92. physics

    What is the ratio of the gravitational force on you when you are 5800 km above the Earth's surface versus when you are standing on the surface? (The Earth's radius is about 6400 km.)
  93. Physics [No Math]

    When calculating weights away from Earth's surface, for example: At 6.38x10^3 km away from Earth's surface a spacecrafts weight is d=rE+rE Then F=(1/4)(SpaceCraftWeight) Why is the distance 2rE?
  94. Physics

    calculate the escape velocity on the surface of earth, acceleration due to gravity will be 36 percent of its value on the surface of earth .if mean radius is 6400 km?
  95. physics

    A 70 kg man weighs 686 N on the Earth's surface. How far above the surface of the Earth would he have to go to "lose" 14% of his body weight? i don't even know where to start with this question... i need help!
  96. science help PLS

    Which of the following correctly describes a way in which Earth’s atmosphere interacts with the hydrosphere? Living organisms breathe gases in the atmosphere. Water moves between Earth’s surface and the atmosphere. Gases in the atmosphere trap incoming
  97. science

    how do the fluxes of radiation help explain why air temperature near the earth's surface is higher than it is 2km above the earth's surface
  98. physics

    with what velocity must a body be thrown from earth surface so that it may reach a height 4Re the earth surface. given Re=6400km g=9.8m/s
  99. Physics

    A man has a mass of 80kg on the Earth's surface. Part A How far above the surface of the Earth would he have to go to "lose" 13% of his body weight?
  100. Physics

    Al the astronaut has a weight of 1600 N when he is standing on the surface of earth. What is the force of gravity action on him when he is in space station orbiting earth at a distance of four earth radii from the center of the earth?