1. Math

    Can someone please help me set this up. I didn't quite understand how to do this today. Before leaving Earth, the mass of an astronaut is measured to be 60kg. The astronaut lands on the Moon and measures the acceleration of gravity to be 1.6 m/s2(squared).
  2. physics

    The planet Jupiter is more than 300 times as massive as the Earth But it so happens that a body would scarcely weigh three times as much on the surface of Jupiter as it would on the surface of Earth. Can you think of an explanation for why this is so?
  3. Maths

    The earth is approximately a sphere of average diameter 12740km. The smallest of the planets is Mercury, also spherical, with average diameter 4840km. Determine what percentages (to the nearest hundredth) the volume and surface area of Mercury are of those
  4. Science

    Planets shine by reflected sunlight. How can planets be brighter than stars? Approxinmately how many times brighter than Mars is Earth's full moon? (i do know the Moon's apparent magnitude equals -12.6) Could we see the sun if it were 32.6 light years from
  5. physics

    The planet Jupiter is more than 300 times as massive as the Earth But it so happens that a body would scarcely weigh three times as much on the surface of Jupiter as it would on the surface of Earth. Can you think of an explanation for why this is so?
  6. Phyics

    The average distance between Earth and the sun is 1.50e8 km. Calculate the average speed, in km/h, of Earth assuming a circular path about the sun. Use the equations v = 2r/T. Please ignore this question and view the question I have a few spaces above. The
  7. earth science am i right?

    am i right 19. According to the law of __________, only a worldwide flood with its vast complex of sediment-saturated currents would produce horizontal superimposed layers of materials, thus forming a great series of sedimentary strata formed in various
  8. Astronomy - help!

    The earliest fossil records indicate that life appeared on Earth about a billion years after the formation of the solar system. What is the most mass that a star could have in order that its life-time on the main-sequence is long enough to permit life to
  9. physics

    About 50,000 years ago, in an area located outside Flagstaff, Arizona, a giant 4.5x10^7 kg meteor fell and struck Earth, leaving a 180 m hole now known as Barrington crater. If the meteor was traveling 20000 m/s upon impact, with what average force did the
  10. Math

    Select all the true statements about identities. A) You may use proven identities to prove other identities. B) An identity is true only for restricted values of the variables. C) You can prove an identity by graphing the side to the left of the equal
  11. science

    The atmosphere is composed of a mixture of _______________, _____________ ____________, and tiny___________________. Thank you for using the Jiskha Homework Help Forum. The origin of our atmosphere is still open to a great deal of speculation. One theory
  12. Physics

    Calculate the position of the center of mass of the following pairs of objects. Use a coordinate system where the origin is at the center of the more massive object. Give your answer not in meters but as a fraction of the radius as requested. Get data from
  13. physics

    Using Newton's Law of Universal Gravitation, compare the effect of the Sun and the Moon on the tides. Constants: Mass of the Moon, M☽= 7.348E22 kg. Moon's semi-major axis, a☽= 3.844E8 m. You can find the other constants you will need on the
  14. Astronomy

    1. What color are stars that are very hot and very bright? A. Red B. Blue C. White D. Yellow 2. During the contraction of a protostar, density increases and ______ rises. A. Nuclear energy B. Dust C. Temperature D. Outflow 3. What is the apparent
  15. meteorology

    Compared to the planet's average radius (6371 km or 3959 mi), the atmosphere is like the thin skin of an apple. About 99% of the atmosphere's mass occurs within about 32 km (20 mi) of Earth's surface. Hence, the thickness of the atmosphere represents only
  16. physics

    You weigh 516 N at sidewalk level outside the World Trade Center in New York City. Suppose that you ride from this level to the top of one of its 410 m towers. Ignoring Earth's rotation, how much less would you weigh there (because you are slightly farther
  17. physics

    A pendulum clock that works perfectly on Earth is taken to the Moon. (a)Does it run fast or slow there? (b) if the clock is started at 12:00:00 am, what will it read after one Earth day(24hrs)? Assume that the free-fall acceleration on the Moon is 1.63
  18. Physics

    It can be shown that for a uniform sphere the force of gravity at a point inside the sphere depends only on the mass closer to the center than that point. The net force of gravity due to points outside the radius of the point cancels. Part A How far would
  19. Physics

    Supposed a skydiver ( mass=75kg ) is falling toward the earth. When the skydiver is 100m above the earth he is moving at 60m/s. At this point calculate the skydiver: Gravitational potential energy Kinetic energy Total mechanical energy
  20. chemistry

    Radio waves travel at the speed of light which is 3.00 x 108 m/s. How many minutes does it take for a radio message to reach Earth from Saturn if Saturn is 7.9 x 108 km from Earth?
  21. math

    2.If a sledgehammer that weighs 18 newtons on Earth will weigh about 4 newtons on the planet Namar, then your weight on Namar would be about ___ times your weight on Earth. A. 0.25 B. 4 C. 0.5 D. Not enough information
  22. maths

    If the speed of light is 3x10^8m/s and the distance around the earth is 4.5x10^4 km and a plane could travel at half a speed of light, how long would it take for the plane to fly around the earth twice?
  23. Math

    A year on Mars is 1.88 Earth years. If you are 13 years old on Earth, how old would you be on Mars? I don't know if I am supposed to multiply or divide. I also don't understand what the question is trying to state. Thanks
  24. physics

    How do I calculate the radial acceleration in g's? For example: Calculate the radial acceleration (in g’s) of an object on the ground at the earth's equator, turning with the planet. Earth's radius is 6380 km.
  25. physics

    The first Lunar Olympics is to be held on the Moon inside a huge dome. Of the usual Olympic events - track and field, gymnastics, and so on - which would be drastically affected by the Moon's gravity? In which events would Earth=based records be broken? In
  26. Physics Problem 6.20

    The center of a 1.40 km diameter spherical pocket of oil is 1.50 km beneath the Earth's surface. Estimate by what percentage g directly above the pocket of oil would differ from the expected value of g for a uniform Earth? Assume the density of oil is
  27. physics

    Gravity on the moon is only 1/6 as strong as gravity on the Earth. What is the weight of a 16 kg object on the moon and on the Earth?
  28. physics

    Gravity on the moon is only 1/6 as strong as gravity on the Earth. What is the weight of a 16 kg object on the moon and on the Earth?
  29. physics

    Light from the Sun reaches Earth in 8.3 min. The speed of light is 3.00 x 10^8 m/s. How far is Earth from the Sun?
  30. Physics

    A tennis ball on Mars, where the acceleration due to gravity is 0.379 of a and air resistance is negligible, is hit directly upward and returns to the same level 9.50 later. How fast was it moving just after being hit? The formula is the same as we use on
  31. Physics

    I have a hard time solving this problem. The weight of an object at the surface of a planet is proportional to the planet's mass and inversely proportional to the square of the radius of the planet. Jupiter's radius is 11 times Earth's and its mass is 320
  32. Physics

    If you weigh 670 N on the earth, what would be your weight on the surface of a neutron star that has the same mass as our sun and a diameter of 15.0 km ? Take the mass of the sun to be ms = 1.99×1030 kg , the gravitational constant to be G =
  33. physics

    Determine the force per meter on a lightning bolt at the equator that carries 20 000 A and is perpendicular to the Earth’s magnetic field, 3x10-5 T. What is the direction of the force if the current is straight up and the Earth’s field direction is due
  34. physics

    Determine the force per meter on a lightning bolt at the equator that carries 20 000 A and is perpendicular to the Earth’s magnetic field, 3x10-5 T. What is the direction of the force if the current is straight up and the Earth’s field direction is due
  35. Precalculus

    A nautical mile equals the length of arc subtended by a central angle of 1 minute on a great circle on the surface of Earth. If the radius of Earth is taken as 3960 miles, express 1 nautical mile in terms of ordinary, or statute, miles.
  36. Socials

    John. A Macdonald for Confederation... For 20 long years, I have been dragging myself through the dreary waste of Colonial politics. I thought there was no end, nothing worthy of ambition; but now I see something which is well worthy of all I have suffered
  37. Physical Science

    Galaxy A is 600 million light years from earth. Galaxy B is moving away from the earth at a speed that is 80% as large as that of Galaxy A. How far from earth is Galaxy B? A. 750 million light years. B. 640 million light years. C. 540 million light years.
  38. Astronomy

    Hi, can you please check my work? I really need to do well on this. 1. What properties of a star are needed to calculate the stars luminosity? a. size and apparent brightness b.mass and distance to the star**** c. temperature and diameter of the star d.
  39. Please CHECK thanks

    Please check and tell me what I got wrong and let me know the correct answer for the problem. Thanks. 1. Diarrhea can be caused by a change in diet and different minerals in the water. True (yes) False 2. Fusion produces less radioactivity than fission.
  40. math

    THE DISTANCE FROM EARTH TO MOON IS ABOUT 22^4 MILES . THE DISTANCE FROM EARTH TO NEPTUNE IS ABOUT 22^7 MILES . WHICH DISTANCE IS GREATER ? ABOUT HOW MANY TIMES GREAT ?
  41. physics

    Planet X has the same mass as earth, but its radius is only half as big. How does the gravity on this planet compare with the gravity on our planet earth?
  42. Pysics

    Planet X has the same mass as earth, but its radius is only half as big. How does the gravity on this planet compare with the gravity on our planet earth?
  43. Physics

    a space-satellite mass of 600kg fires a rocket engine for 2 seconds expelling 40kg of exhaust gases at 350m/s. By how much will the speed of the capsule change? You may consider the initial relative velocities to be zero, but would it matter?
  44. Math

    Research two satellite phone plans with a specific number of minutes a month. Create a linear equation to represent the monthly bill based on both the flat fee and the per minute cost. Which one is the better option? Why?
  45. Math

    Research two satellite phone plans with a specific number of minutes a month. Create a linear equation to represent the monthly bill based on both the flat fee and the per minute cost. Which one is the better option? Why?
  46. Biology

    Pick the BEST answer: A)Which Of The Following Is An "Excitable Cell"? <4>1) Neuron <3>2) Electron <4>3) Hormone <3>4) Both 1 & 2 <4>5) All Of The Above B)What Is The Popular Molecule That Energizes Many Activities In Cells?
  47. English

    1. We will lead your children to the joys of reading. 2. We will lead your children to the joy of reading. 3. We will lead your children to joy of reading. (Which expressions are grammatical? Are both acceptable?) 4. I learn many things in class from her
  48. physics

    A mass is suspended on a spring scale. The scale shows a reading of 5N and stretches a distance of 0.2 meters from its relaxed length. 1)What is the spring constant of the scale? )If this scale was taken to a planet that has a mass 4 times larger than the
  49. Physics

    What astronomical event would be seen by observers on the Moon at the time the Earth experiences a lunar eclipse? At the time the Earth experiences a solar eclipse?
  50. Earth and Environmental Science

    How much does the amplitude of the waves increase between an earthquake that measures 4.2 on the Richter scale and an earth quake that measures 6.2 on the Richter scale?
  51. Physics

    The acceleration of gravity at the surface of the moon is approximately 1/6 that at the surface of the Earth (9.8m/s). What is the weight of an astronaut standing on the moon whose weight on Earth is 180lbs?
  52. science

    The gravitational pull on Jupiter is 2.5 times greater than Earth's gravitational pull. If an object weighs 10 pounds on Earth, what will it weigh on Jupiter?
  53. Science

    The speed of light is 3 x 10 to the 8th power meters per second. If the sun is 1.5 x 10 to the 11th power meters from earth, how many seconds does it take light to reach the earth?
  54. Physics

    a 4 kg object is taken to a planet that has 3 times the mass of earth and 1/2 the radius of earth. On this planet the mass of the object will be most nearly.. A. 12kg B. 3kg C. 48kg D. 4kg E. 24 kg
  55. Physics 1111 at UGA

    If a projectile is launched from Earth with a speed equal to the escape speed, how high above the Earth's surface is it when its speed is one third the escape speed?
  56. Algebra

    Your weigh on the moon is about 1/6 of your weigh on earth. Write and solve an equation to show how much a person weighs on earth if he weighs 16 lbs. on the moon .
  57. earth

    On planet Tehar, the free-fall acceleration is the same as that on Earth but there is also a strong downward electric field that is uniform close to the planet's surface. A 2.00 kg ball having a charge of 5.00 µC is thrown upward at a speed of 29.2 m/s
  58. Earth Science

    I am struggling with these two questions I have looked all over the internet && even my science book but still no answers...thank you to anyone that can help. ♥ What is unique about Earths position in the Solar system as it relates to water, and why
  59. Somebody check this plz..and thanks.

    Please check and tell me what I got wrong and let me know the correct answer for the problem. Thanks. 1. Diarrhea can be caused by a change in diet and different minerals in the water. True (yes) False 2. Fusion produces less radioactivity than fission.
  60. science

    i have to do a homework assignment on how the earths orbit and tilt are causing global warming and i cant find anything but greenhouse effect please help. i gotta turn this in tomarrow
  61. physics

    A proton with charge mass ratio of 108 C/kg is moving in a circular orbit in a uniform magnetic field of 0.5T .Calculate the frequency of revolution.
  62. Physics

    A 5.00 x 102 kg hot air balloon takes off from rest at the surface of the earth. The buoyant force lifts the balloon straight up, performing 9.70 x 104 J of work on the balloon. At the instant the balloon's upward speed is 4.08 m/s, the balloon will be
  63. Physics

    The drawing (not to scale) shows one alignment of the sun, earth, and moon. The gravitational force that the sun exerts on the moon is perpendicular to the force that the earth exerts on the moon. The masses are: mass of sun=1.99 × 1030 kg, mass of
  64. Science/Biology

    Pick the BEST answer: A)Which Of The Following Is An "Excitable Cell"? <4>1) Neuron <3>2) Electron <4>3) Hormone <3>4) Both 1 & 2 <4>5) All Of The Above B)What Is The Popular Molecule That Energizes Many Activities In Cells?
  65. Physics Using hydrostatic equilbrium)

    3. A model of Earth’s interior: Look up the radius and mass of the Earth. Radius is 6,371 km Mass is 5.974 x 10^24 kg Calculate its average density. p_e = (5.974 x 10^24 kg)/ (4/3)pi r^3 = (5.974 x 10^24 kg)/ (4/3)pi (6371)^3 = 5.54 g/cm^3 Using this
  66. science

    Will we ever run out of air? Air is stuck to the planet by gravity, it won't leave. Two things are adding to the air all the time too, the planet is always releasing gasses from volcanoes and volcanic vents, and there are some meteors that are mostly ice
  67. 7th Grade Math

    The weight of an object on the moon varies directly as the weight of the object on Earth.A 90-pound object on Earth weights 15 pounds on the moon.if an object weights 156 pounds on Earth, how much does it weights on the moon? A.23 pounds B.26 pounds C.28
  68. science !!!!

    does anybody know some quick facts about earth science (Broken Link Removed)
  69. astronomy

    A body has four times the mass of the Earth but its radius is two times larger. What is the acceleration of gravity on the surface of this planet? If you were on this planet, should you be able to jump (on average) farther distances, shorter distances or
  70. Math

    A probe launched from Earth to Mars is traveling at an average speed of 1.8 * 10^4 kilometers per hour. If the distance between Earth and Mars is approximately 2.25 * 10^6 kilometers, about how many hours will it take the probe to reach Mars? PLEASE
  71. Physics

    Suppose a cylindrical platform with moment of inertia 0.005kg m2 is freely rotating at angular speed 10 rad/s. A disc initially, rotationally at rest with mass 0.6kg and radius 0.1 m is dropped onto the platform so that their centers coincide. The kinetic
  72. physics

    Goku wants to visit Andromaeda galaxy which is 2 million light years away from earth. If it takes 30 years in the frame of the spaceship to travel to Andromeda from earth, what should be the speed of the spaceship? Assume that the spaceship travels at
  73. 5th grade

    one light year is about 9 trillion kilometers . arctus is a star that is 37 light years from earth.if you are 11 years old now,how old will you be when light that is leaving arcturus today reaches earth. how far in kilometers willit have traveled .sow your
  74. 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
  75. Science Ms. Sue?

    Why did the following change occur? The snow that covered the ground all winter began to melt, temperatures rose, and flowers started to bloom. A. days became shorter B. the Earth tilted away from the sun C. the sun's rays became more concentrated D. Earth
  76. earth

    On planet Tehar, the free fall acceleration is the same as that on the Earth, but there is also a strong downward electric field that is uniform close to the planets surface. A 2.00k ball having a charge of 5.00C is thrown upward at a speed of 20.1 m/s. It
  77. Thomas Malthus

    Thomas Malthus was a clergyman so is it safe to say that he did not believe in anything opposing the bible? Is it safe to say that as a firm believer in faith, he was certain that God created the Earth and the life on it? What can i say about Malthus's
  78. physics

    A rocket cruising past earth at 0.800c shoots a bullet out the back door,opposite the rocket's motion,at 0.900c relative to the rocket. What is the bullet's speed relative to the earth?
  79. 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
  80. Physics

    The mass of an astronaut is 72kg. (a) what is his weight on earth ( taking g to be 10N/kg) ? (b) if the astronaut is on the moon's surface where the acceleration due to gravity is one-sixth on the earth , calculate (I) the mass (ii) the weight of the
  81. main idea

    The main conclusion you can draw from this paragraph is that A. because of the greenhouse effect, plants on Earth should thrive. B. a greenhouse helps plants to grow faster. C. the atmosphere keeps Earth warm D. in a greenhouse, the Sun's heat is trapped
  82. physics

    if the angular speed of earth becomes 17times its present value what will be the 1.effect on a body on the equator of earth? it will be A. Heavier than present value B.lighter than present value C.weightless And also what is the reason? 2.a girl sitting on
  83. physics

    if the angular speed of earth becomes 17times its present value what will be the 1.effect on a body on the equator of earth? it will be A. Heavier than present value B.lighter than present value C.weightless And also what is the reason? 2.a girl sitting on
  84. Earth Science

    I need help with igneous rocks and the rock cycle. Is there a web site that will help me. One question is When magma cools below Earth's surface, it forms __________-grained, _________ igneous rocks. fine grained for your other word read:
  85. Physics

    (a)Assuming that only gravity is acting on it, how far does an electron have to be from a proton so that its acceleration is the same as that of a freely falling object at the Earth’s surface? (b)Suppose the Earth were made up only of protons but had the
  86. math

    Please check my math answers (and correct?)? I have some math questions, please check them, (they are multi choice, check if my answer is correct. if not, please say which is correct) 1. What is the simplified form of the expression –(10)–1? a -1/10 b
  87. physics

    on the surface of earth, a spacecraft has a mass of 2.00x10^4 kilograms. What is the mass of the spacecraft at a distance of one earth radius above earths surface?
  88. earth

    Find the ratio of the gravitational attraction between (a)a man of mass 100 kg and a woman of mass 50 kg who is 10 meters away from him and (b) the attraction between the woman and the Earth.
  89. Science

    Here is a question on my science worksheet, "if a projectile's fall matches Earth's 'BLANK', the projectile will not hit earth." i need help figuring out what would go in the blank!
  90. Physics

    Light from the Sun reaches Earth in 8.3 min. The speed of light is 3.00 x 10^8 m/s. How far is Earth from the Sun? GIVEN: t = 8.3 min V = 3.00 x 10^8 m/s --> Would acceleration be 9.81 m/s^2? Is it this equation d = Vit + 1/2 a t^2
  91. math

    Asia is about 3 times the size of antarctica together the 2 continents make up 2/5 of earth's land . what fraction of earth's land does antarctica make up?
  92. physics

    weight of a person in newton on mars who weigh 882N on earth ( g = 9.8m/s^2). weight of person on earth who weighs 333N on mars.
  93. physics

    The Sun and Earth each exert a gravitational force on the Moon. What is the ratio FSun/FEarth of these two forces? (The average Sun-Moon distance is equal to the Sun-Earth distance.)
  94. Physics

    What is the speed of the rocket when it is 350 above the surface of the earth? A rocket starts from rest and moves upward from the surface of the earth. For the first 10 of its motion, the vertical acceleration of the rocket is given by a(y)=2.9, where the
  95. English Writing

    People believe in God because... And there is life on earth because... And people who believe in God think that God has put human beings on this earth because... Could you help me? I'm not English speaker so I don't know how can I write continue of these
  96. Physics

    Take the radius of the earth at the equator to be 6380 km a. Find the speed the speed of an object at the equator due to the earth's rotation. ___m/s b. Convert this speed to miles/hour (show your conversion factor in your written backup). __miles/hour
  97. Physics

    Take the radius of the earth at the equator to be 6380 km a. Find the speed the speed of an object at the equator due to the earth's rotation. ___m/s b. Convert this speed to miles/hour (show your conversion factor in your written backup). __miles/hour
  98. ENGLISH Types of business writing

    Assume that you’ve worked for the last five years as an administrative assistant for the Human Resources Department of Broadworth General Hospital. The Director of Human Resources, Miriam Hopkins, has charged you with organizing a two-hour training
  99. reading

    (1) Scientists generally agree that Earth is getting warmer due to what's called the greenhouse effect. (2) A greenhouse stays warm because sunlight and heat coming through the glass roof are mostly trapped. (3) The heat doesn't radiate back into the
  100. math

    The planet Mercury travels 180,600 miles in its orbit during the 7 hours that make up a typical school day. Find the unit rate.