# Earth

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

english
:Select the correct excerpt. Which excerpt from Robert Stawell Ball's Great Astronomers is best supported by this diagram? The diagram show the earth in the middle the sun circling it then the moon circling earth but farther away with mars circling the moon Excerpt 1 These ...

Science- Astronomy
How are Earth and Venus different? I already wrote that they have different atmospheres but I need another reason why are different so can someone help me please?

Science
Why is the weight of an object less on the moon than on Earth?

science
Earth's energy sources include both renewable and nonrenewable resources. name at least three sources of energy that could be used in your house. then describe the ideal energy source for generating most of your home's electricity, and explain why you choose that source

Math
There is a population of 6.848 billion people. There are roughly 57.9 million square miles of land on Earth, of which about 22% are favorbale for agriculture. Round answer to the nearest person. There are ___ people/ mile^2 of farmable land. I DIVIDED 6.848BILL / 57.9MILL & ...

biology
would it be easier if someone who doesn't have proprioception to go to space and return back to earth to walk normally or would it be the same?

maths
Angle of elevation of sun from earth is called? (A) sunset (b) sun's altitude (c) sunrise (d) none

science
1. Which is not a characteristic of the group 1 alkali metals? A. High densities B. Low melting points C. Found in batteries D. Silvery solid 2. which of the following is true of the group 2 alkali earth metals A. they are less dense that the group 1 alkali metals b. They have...

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 -1/-1^10 (my answer) ...

Language Arts
The arrow and the song poem 1 i shot an arrow into the air, 2 it fell to earth, i know not where; 3 for, so swiftly it flew, the sight 4 could not follow in its flight Part A Which form best describes the poem this excerpt is from A. lyric poem B. concrete poem *** C. haiku D...

Science- Earth
Under which circumstances do neap tides occur? HELP NEED ASAP!!

Physics
Sputnik, the first artificial satellite to orbit the Earth, had a mass of 83.6kg and travelled at 7574 m/s. The radius of the earth is 6371 km and its mass is 5.972 x 10^24 kg. What gravitational force did Sputnik apply to the earth during this orbit? What I've got so far: so...

Math - Calculus
Directions (or bearings) on Earth are measured in degrees, running from zero to 360 degrees, clockwise, starting with 0 degrees being due North. So due East for example, is 90 degrees, due South 180 degrees, and Northwest is 315 degrees. You are swinging a rock clockwise (...

Science
Ozone is known to cause respiratory problems in humans and to damage plants. However, the ozone layer also protects Earth. Explain the locations ozone can be found, how ozone is helpful, how it is harmful, and what causes the depletion of the ozone layer.

physics
A flying-saucer shaped fairground ride is rotating in a horizontal plane. If the rider’s circular path has a radius of 8 m, at how many revolutions per minute the ride should spin in order for the rider to feel a centripetal acceleration of about 1.5 times Earth’s ...

Physics
which of the following is NOT true about the path of a cannon ball launched horizontally from the earth's surface if air resistance is neglected? a. the cannnonball has a uniform horizontal velocity b.the total velocity of the cannon ball increases as a function of time c.the ...

physics
The Earth is 150 million km from the sun. It completes one orbit in a period of approximately 365.25 days. Calculate the orbital speed of Earth in km/hour. please helpppp

science
a body is released from the great height and falls freely towards the earth . another body is released from the same height , one second later . then the separation between the two bodies , two seconds after release of the second body is

Science
The words to use are: crust, moving, lithosphere, asthenosphere, upper mantle, volcanoes, semisolid The ___1___, which includes the ___2___ and part of the ___3___, is divided into plates that carry all of Earth's lands and oceans. These plates float on a ___4___ layer of rock...

Physics (Magnetism)
In an experiment on the shuttle, an electron with a speed of 6.3 x 105 m/s [N] and a mass of 9.11 x 10-31 kg is shot through an external magnetic field. Determine the strength and orientation of the magnetic field required so that the electron's direction of travel remains ...

Earth Science
Slide 1 This is a cumulus cloud. Can you find four things on the word list that you can use to describe this cloud. Cumulus clouds consists of puffy tops, no rain expected, 3,000 ft. high, and flat bottoms. Slide 2 This is an example of towering cumulus clouds. Write down as ...

Science and Hurry!
What causes land breeze and sea breeze? A) The differential heating of land and sea by the Sun results in the movement of air. B) Hot air from the sea blows over the land because there is a high pressure area over the sea. C) Cold air blows from the land over the sea because ...

Some Polynesian islands are ring-shaped coral islands that surround a body of water, or (1 point) • copra. • coral. • atolls. • plates. 2. In the mid-1800s, what event played a part in the large increase in British immigration to Australia? (1 point) • Aborigines ...

1. How does sea-floor spreading occur? a.New materials are being added to the atmosphere. b. Earthquakes break apart the ocean floor. c. Sediments accumulate at the area of spreading. d. Molten material beneath Earth's crust rises to the surface. 2. Which feature form the ...

Physics
Hi, I'm stuck with the following question: The acceleration due to gravity on Mars is only 3.75m/s^2. You would like to modify an antique grandfather clock so that it would still keep accurate time on Mars. If the length of the pendulum on Earth is l, what should the length of...

physics
calculate angular momentum and rotational kinetic energy of earth about its own axis

physics
A ball is let fall from a hight h0.There are n collisions with the earth . If the velocity of rebound after n collisions is vn and the ball rises to a hight hn , then coefficient of restitution e is given by ,

algebra
Astronomers measure large distances in light-years. One light-year is the distance that light can travel in one year, or approximately 5.88 *10^12 miles. Suppose a star is 3.2 * 10^2 light-years from Earth. In scientific notation, approximately how many miles is it? 1.88 * 10^...

Science
The force of gravity of objects on the moon is approximately one-sixth of their value on Earth. Joe's weight on the moon is 124 N. What will Joe's mass on Earth be?

Science
The force of gravity of objects on the moon is approximately one-sixth of their value on Earth. Joe weighs 7633 N on earth. What will Joe's mass on the moon be?

Science
Which of earth's spheres contains mountains,valley's, and other landscapes?

SCIENCE asap :P
Twice a year on Earth, the number of hours of darkness is equal to the number of hours of sunlight. These events, where both day and night are 12 hours, are the spring and autumn equinoxes.Which of these describes the orientation of the sun and Earth on these two days? A.Earth...

Earth Science
1. We start with 400 atoms of Uranium-238. How many remain after 4.5 billion years? _______ After 9 billion years? _______ After 13.5 billion years? ________ 2 . How long will it take for ½ of the original amount of Rubidium-87 to decay? _______ 3. Carbon-14 has a half-life ...

English
A character who is depicted realistically and has his or her own personality and history in a story is what type of character? A. Individuated B. Main == C. Modern D. Representative Which of the following is not considered a level of setting in a story? A. Supernatural B. ...

Science
Physics A scientific instrument weighing 98 pounds on the Earth is transported to another planet whose mass is 1.7 Earth masses and whose radius is 0.7 Earth radii. What does this instrument weigh on this planet? To be graded correctly, enter the new weight in pounds (numbers ...

Geometry
A sailboat is heading directly north at a speed of 16 knots (1 knot = 0.514 m/s). The wind is blowing towards the east with a speed of 10.4 knots. (Both velocities are given relative to the Earth.) Determine the magnitude and direction of the wind velocity as measured on the ...

Science
Carrying capacity is the maximum number of ___________ that an ecosystem can support 1.different species 2.individuals in a population**** 3.habitats 4.limiting factors In an island ecosystem, a species of beetle feeds on leaves of a shrubby plant. A species of songbird preys ...

Geologic Time and Earth's History Unit Te
1. An example of a geologic event that could be recorded in rocks is ____. a civil war the occurrence of sun spots a volcanic eruption a lunar eclipse 2. "The present is the key to the past." This statement rephrases the ____. principle of cross­cutting relationships law of ...

physics
what is gravitational field of the earth?

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

physics
The earth spins on its axis once a day and orbits the sun once a year (365 1/4 days). Determine the average angular velocity (in rad/s) of the earth as it (a) spins on its axis and (b) orbits the sun. In each case, take the positive direction for the angular displacement to be...

Science
During a lunar eclipse, does the Moon enter the Earth’s shadow from the east or the west? Explain your answer. Wouldn't it be the east because that's the same way the moon rises normally? So if it normally rises in the east it would do that again.. or would it be west ...

Literature
which of the following lines from song of becoming best supports the response selected above? A:"Facing sullen tanks with streams of stones. B: Dueling with branches, pretending to be great heroes in history. C: They grown to become trees, plunging deep roots into the earth...

science
The orbits of planets being elliptical was one the planetary laws developed by ==A. Kepler. B. Brahe. C. Ptolemy. D. Copernicus. If a car travels from Town A to Town B on one road at different speeds and stops at red lights, knowing the distance between the towns and the ...

Math
A variable star is one whose brightness alternately increases and decreases. Lists of variable stars can be found online, and many occur in familiar constellations visible with the naked eye. One such star, R Hydrae, has an average magnitude rating of 7.2 but its magnitude ...

math
Describe the points on the earth’s surface that are visible to a viewer who is 100 miles above the North Pole. Would it be half of the surface area of Earth?

Science
The (blank) has given scientists information about past life on Earth.

Earth Science
What are the maximum and minimum dimensions (the size range) for the following particle sizes? a) cobble: b) pebble: c) sand: PLEASE HELP

Math show work
If a hypothetical planet in our Solar System had a sidereal period of 11.1 Earth years and a circular orbit, how far from the Sun in Astronomical Units would it be? Enter your answer to the nearest 0.01 AU.

Math
If a hypothetical planet in our Solar System had a sidereal period of 11.1 Earth years and a circular orbit, how far from the Sun in Astronomical Units would it be? Enter your answer to the nearest 0.01 AU.

physics
IF a particular galaxys has a total mass of 10 to the 56 grams and the average star in that galaxy has a mass of 10 to the 35 grams, approximately how many stars are there in that galaxy? Give your answer to the nearest whole power of 10 by entering the exponent only. A ...

Math
If an object which weighs 100 lbs on the Earth's surface were placed on a planet with 2 times the radius of the Earth and with 7 times the Earth's mass, how much would that object weigh? Enter answer to nearest 0.1 lbs. The term "void ratio" means the ratio of the volume of ...

physics
1.A certain spacecraft is 3.3 AU (Astronomical Units) from Earth. How long in seconds does it take for a signal to reach the Earth after it is transmitted from the spacecraft? Hint: An AU is about 149.9 Million Km, and light moves at 299,800 Km/s. {Indicate your answer to the ...

English
What is the meaning behind this quote: you've gotta dance like there's nobody watching love like you'll never be hurt sing like there's nobody listening and live like it's heaven on earth

Astronomy
1. How did the geocentric model explain the retrograde motion of planets? A. Earth moves faster in its orbit and passes the other planets. B. The planets move backward when they get too close to earth. C. The planets travel in circles as they move around earth in a circle. D. ...

Physics
Many astronomers argue that the Earth and Moon should be considered a double planet,since the gravitational force by the sun on the Moon is approximately as big as that by the Earth on the moon.Using the data below for the Earth and Moon at the particular point in their orbits...

Physics 20
Astronomers launch a satellite to explore a nearby asteroid that has come dangerously close to the earth.The satellite begins orbit around the earth,with an orbital radius 6.85 X 10^3 Km, before being moved to an orbit about the asteroid with a period of 9.06 X 10^3 S at a ...

Physics 20
Astronauts in orbit appear to be 'weightless'.Suppose an astronaut with a mass of 154 KG including gear is in orbit in the space shuttle, a distance of 222 km above the Earth;s surface.Taking the Earth's radius to be 6371km, and its mass to be 5.97 X 10^24, A) What is the ...

eng
the primary purpose to al gore's an inconvenient truth is a. to inform the readers that there is environmental hazard in burning fossil fuels b. to entertain readers with stories from his college days and his professor's quotations c. to persuade the readers that by taking ...

Physics
A helicopter is ascending vertically with a speed of 5.20 m/s. At a height of 125 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground? [Hint: The package's initial speed equals the helicopter's.]

Science
Which of these statements are true? A. There is more water on Earth now than there was millions of years ago. B. There is less water on the Earth than there was millions of years ago.(MY ANSWER) C. There is no way to tell how much water there was on Earth millions of years ago...

Chemistry
Write the symbol for the elements that fit the following descriptions 1. 10 electrons in each -3 ion 2. 18 electrons in each +2 ion 3. The alkaline earth metal in the third period

English
Description: does anyone has teas 6, the new version , passage about new York central park, earth cousin, or time management , if i anyone has it let me know am willing to pay anything for it

physics
The mass of the Earth is 5.98 × 1024 kg. A 6.83 kg bowling ball initially at rest is dropped from a height of 2.12 m. The acceleration of gravity is 9.8 m/s^2. What is the speed of the Earth coming up to meet the ball just before the ball hits the ground? How do you solve this?

Dynamics
A level fight bomber flying at 300 ft/s releases a bomb at an elevation of 6400 ft. Approximately how long before the bomb strikes the earth?

IPC
The value of acceleration due to gravity (g) on a point 10,000 kilometers above sea level is about 1.49 meters/second2. How much will an object, which weighs 98 newtons on the surface of Earth, weigh on this point? The value of acceleration due to gravity on Earth is 9.8 ...

Maths
The speed of a point A due to the rotation of the earth is twice that of a point B.If A is on latitude 22°N.calculate the latitude of B

Earth science
Most of the sand that makes up the sandstone found in New York State was originally deposited in which type of layers?

Physics
the orbital period of the moon is 27.32 days. The international space station has an orbital period of 90 minutes. What is the mean distance between the center of the earth and the center of the international space station? moons orbital radius: 25,201

Math, Physics
Calculate Earth's gravitational force on the ISS astronauts while orbiting at an altitude of 401.5 km above Earth’s surface.

Maths
I posted yesterday but feel I confused the issue with an incorrect calculation of an angle, I have just realised my mistake!. I also think I should come clean about my circumstances. I am a mature (very) student, in fact a retired commercial fisherman and am studying celestial...

LA
PLEASE check my answer this is my last test and i d not want to mess up PLEASE 1. Which sentence contains an opinion? (1 point) Thomas Jefferson supported American independence from Great Britain. He was a lawyer in his home state of Virginia. Jefferson authored the ...

math
p=14.63⋅0.8 Atmospheric pressure, measured in pounds per square inch p, s, i is the force exerted by Earth's atmosphere over a given area. The atmospheric pressure, p, exerted on an airplane flying at an altitude of a miles above sea level can be approximated by the model ...

science
An astronauts boots weigh 100N on earth where the acceleration of free fall is 10m/s2. How much will they weigh on Mars where the acceleration of free fall is 4m/s2?

science
An astronauts boots weigh 100N on earth where the acceleration of free fall is 10m/s2. How much will they weigh on Mars where the acceleration of free fall is 4m/s2?

Chemistry
Which of the following is true about oxidation reactions? A. Oxidation reactions are the principal source of energy on Earth. B. All oxidation reactions are accompanied by reduction reactions. C. The burning of wood in a fireplace and the metabolization of food by your body ...

science
if yourweight is 60N on earth,how far should you go from the center of the earth so that your weight will be 300N

Pre-calc Math
The path of a satellite orbiting the earth causes the satellite to pass directly over two tracking stations A and B, which are 95 mi apart. When the satellite is on one side of the two stations, the angles of elevation at A and B are measured to be 87.0° and 84.2°, ...

physics
A geostationary satellite for communications seems to be in a fixed spot above the equator because it has the same angular velocity as the earth.A) show that if it goes round once a day,its angular velocity is a little over 7Ã—10 race to negative 5 rad per second

Social Impact of Technology
Which of these planets is in the so-called “Goldilocks Zone”? A. Earth B. Mars C. Jupiter D. Venus Ans: Earth

physics
At ground level g is 9.8meter per second square. Suppose the earth started to increase its angular velocity. How long would a day be when the people on the equator were just 'thrown off' why is the expression thrown off is a bad one?

Hello, I got an assignment writing persuasive essay why we should save water? Could plz check my essay and guide me if I need to change anything. Thank You for your help. Why we should save water. (Persuasive Essay) Have you wondered why we should save water and how we can ...

Science
This is part two of my science I answered the other one just need to be checked on this one and the other one. 10. _________ is the most plentiful fossil fuel in the United States A:Natural Gas B:Coal C:Oil D:Petroleum 11. What is the result of fossil fuels being used more ...

Physics
At ground level g is 9.8m/s^2. Suppose the earth started to increase its angular velocity. How long would a day be when people on the equator were just 'thrown off'? Why is the expression 'thrown off' a bad one ?

Physics
At ground level g is 9.8m/s^2. Suppose the earth started to increase its angular velocity. How long would a day be when people on the equator were just 'thrown off'? Why is the expression 'thrown off' a bad one?

HELP SCIENCE
Luis created a clay model of earth and the sun to show how earth rotates, Luis wants to use a toothpick to represent earths axis of rotation Where should he put the toothpick A - horizontally through earth in the direction earth is traveling B - vertically through the center ...

physics
A. how long will it take for a 55.0 kg steel brick to fall 75 meters on earth. A. how far from the base will a 55.o kg steel brick to land,(horizontally) if it dropped a vertical distance of 75 meters on earth, and what is its velocity just before it hits the ground?

HELP!
Earth's inner core exists at temperatures as high as 7000oC. It exists as a _______ due to the _________. A) solid; high pressure B) liquid; high pressure C) solid; high temperature D) liquid; high temperature

Science
How much you would weigh on the moon if you are 72 pounds on Earth

math
The well is dug 14m deep. Its radius is 2m. The earth dug out is evenly spread out on a rectangular field of dimensions 10m*4m. Find the height of the platform raised.

Science physics
what will be the acceleration due to gravity at up planet whose mass is 8 times the mass of the earth and whose radius is twice that of the earth? g=10

physics
a stone that is thrown near the surface of the earth. There is no air resistance. Position increases in the up direction. The initial velocity is 30 m/s at 30 degrees above the horizontal. what is the velocity when the stone reaches its maximum height ? what is the ...

Chemistry
If an astronaut weights 804n on earth what would he weight on a planet that has 3 times the mass and twice the radius of earth

Science
Which statement best describes a spring tide? A - The periodic rise and fall of the water level in the oceans B - the tide if maximum range that takes place two times a month C - the difference in levels of ocean water at high tide and at low tide D - a rise in ocean water ...

Science
Luis created a clay model of earth and the sun to show how earth rotates, Luis wants to use a toothpick to represent earths axis of rotation Where should he put the toothpick A - horizontally through earth in the direction earth is traveling B - vertically through the center ...

Science
Cassie is writing an equation to show the effect of gravitational pull of the sun and moon on tidal range which equation would Cassie use to show the effect of the sun and the moon on Spring tides? A - sun + moon = spring tides B - sun + Earth = spring tides C - moon - sun = ...

Science
Cassie is writing an equation to show the effect of gravitational pull of the sun and moon on tidal range which equation would Cassie use to show the effect of the sun and the moon on Spring tides? A - sun + moon = spring tides B - sun + Earth = spring tides C - moon - sun = ...

Science
Luis created a clay model of earth and the sun to show how earth rotates, Luis wants to use a toothpick to represent earths axis of rotation Where should he put the toothpick A - horizontally through earth in the direction earth is traveling B - vertically through the center ...

Science
Which statement best describes a spring tide? A - The periodic rise and fall of the water level in the oceans B - the tide if maximum range that takes place two times a month C - the difference in levels of ocean water at high tide and at low tide D - a rise in ocean water ...