Gravitation Questions and Answers
Physics
GravitationThe space shuttle typically orbits 400 km above the earth's surface. The earth has a mass
of 5.98 x 1024 kg and a radius of 6,380 km.
A) How much would a 2000 kg part for the space station weigh when it has been lifte to that orbit in the shuttle's cargo bay?
B) Use your result from part A (or alternatively you can combine the two equations yo now know for Fg) to determine the acceleration due to gravity at that altitude.
Physics
GravitationThe International Space Station is in a 300milehigh orbit.
What is the station's orbital speed? The radius of Earth is 6.37 x 106 m, its mass is 5.98 x 1024 kg.
What is the station's orbital period?
Physics
GravitationTwo satellites of same mass are revolving around a planet of mass M and radius R at heights R and 2R then answer the following questions
Physics
GravitationA body of mass m which is initially at rest at a height R above the surface of the earth of radius R,
falls freely towards the earth, then its K.E. on reaching the surface of the earth is
2 mgR
mgR/2
3 mgR/2
4 mgR
Physics
GravitationWhat happens to the gravitational force between two objects if
a) The mass of one is doubled
b) The masses of both are increased by a factor of 5
c) The distance between them is doubled
d) The distance between them is cut in half
Physics
GravitationTwo masses are attracted by a gravitational force of 19.0 N.
What will the force of attraction be if the distance between the very same two masses tripled?
A. 4.0 N
B. 2.11 N
C. 3.0 N:
D. 5.0 N.
E. 1.33 N
Physics
GravitationWhat is the gravitational force between a 40 kg ballerina, and the Earth at 5.98 x 1024 kg, with a distance of 6.38 x 106 m?
Object 1 (m₂): 40 kg ballerina
Object 2 (m₂): 5.98 x 1024 kg Earth
Distance: (r): 6.38 x 106 meters
Physics
GravitationThe magnitude of the gravitational attraction force that the earth exerts on an 85kilogram person who is 4.0 x 107
meters away from the center of the earth is best approximated by which of the following?
Useful numbers: mearth
5.98 x 1024 kg; G = 6.67 x 1011 Nm²kg²
(a) 21 N
(b) 85 N
(c) 240 N
(d) 830 N

Physics
Gravitation(hrw8c13p51) A comet that was seen in April 574 by Chinese astronomers on a day known by them as the Woo Woo day was spotted again in May 1994. Assume the time between
observations is the period of the Woo Woo day comet and take its eccentricity as 0.11. What is the semimajor axis of the comet's orbit?
Submit Answer Tries 0/8
What is its greatest distance from the sun in terms of the mean orbital radius Rp of Pluto?
Submit Answer Tries 0/8
Physics
GravitationA 4.0 x 104 kg spaceship is at rest in deep space.
Its thrusters provide a force of 1200 kN. The
spaceship fires its thrusters for 20 s, then coasts for
12 km.
▼
Part A
How long does it take the spaceship to coast this distance?
Physics
GravitationThree equal masses are located on a coordinate grid so that the masses and the origin form a square with side length l, as shown in the
figure. Find the magnitude and direction of the gravitational field at the origin due to these masses.
0
9 =
m
m
Find the magnitude of the gravitational field at the origin due to these masses. (Use the following as necessary: m, l, and G.)
Find the direction of the gravitational field. (Give your answer in degrees counterclockwise from the +xaxis.)
o counterclockwise from the +xaxis
Physics
GravitationA satellite with a mass of 125kg is in orbit at a distance of 3.00x106 m above the surface of the Earth.
Mass of
Earth=5.9723x1024kg
Radius of Earth6.378x106m
a. What is the radius of the satellite's orbit?
b. What is the force acting on the satellite?
Physics
GravitationFind the force by the moon on Earth using Newton's Law of Gravitation formula. Their masses are
7.4 x 1022 kg and 6.0 x 1024 kg and it is 3.8 x 108m between their centers.
Physics
Gravitation10. The mass of the moon is 7.35x1022 kg and the mass of the earth is 5.97x1024 kg.
The moon's orbit distance is 3.84x108 m. What is the gravitational force on the
moon by the earth? What is the gravitational force of the earth on the moon?
Physics
GravitationKepler's 3rd law relates the semi major axis of an orbit with its period (the time it takes for the
orbiting body to go around a full cycle). When using units of AU for the semi major axis and years
for the period, Kepler's 3rd law can be written as
(Orbital Period)^2 =(Semi Major Axis)³
or
p² = a³
If Halley's Comet swings around the sun every 75 years, what is the semi major axis of its orbit in
AU units?
Physics
GravitationThe gravitational force the Sun exerts on Earth
A. is always repulsive.
B. is equal in magnitude to the gravitational force the Earth exerts on the Sun.
C. is equal in magnitude to the gravitational force the Earth exerts on the Moon.
Physics
GravitationFinally, consider the gravitational force generated by a spherically symmetrical massive object. The magnitude and direction of such a force are given by Newton's law of gravity:
FG =  Gm1m2r/r^2
where ds = dr r; G, m₁, and m2 are constants; and r > 0. Find
U(rf)U(ro) =∫FG.ds
Express your answer in terms of G, m₁, m2, ro, and rf.
Physics
GravitationEuropa, a satellite of Jupiter, is believed to have a liquid ocean of water (with a possibility of life) beneath its icy surface. In planning a future mission to Europa, what is the fastest that an astronaut with legs of length 0.70 m could walk on the surface of Europa? Europa is 3100 km in diameter and has a mass of 4.8 × 10^22 kg. Express your answer in meters per second.
Physics
GravitationSuppose one night the radius of the earth doubled but its mass stayed the same. What would be an approximate new value for the freefall acceleration at the surface of the earth?
20 m/s²
10 m/s²
2.5 m/s²
5 m/s²
Physics
GravitationA sensitive gravimeter at a mountain observatory finds that the freefall acceleration is 0.0055 m/s² less than that at sea level (9sea level = = 9.83 m/s²).
Physics
GravitationWhich of the following is true about the Universal Gravitational Law?
Force of gravity is directly proportional to the product of masses and also directly proportional to the square
of the distance between them
Force of gravity is inversely proportional to the product of masses and directly proportional to the square of
the distance between them
Force of gravity is inversely proportional to the product of masses and also inversely proportional to the
square of the distance between them
Force of gravity is directly proportional to the product of masses and inversely proportional to the square of
the distance between them
Physics
GravitationNewton's law of gravity describes the gravitational force between
a person and the earth.
the sun and the planets.
All of the listed answers are correct.
Earth and the sun.
Earth and the moon.
Physics
GravitationThe radius of the Earth's orbit around the sun (assumed to be circular) is 1.50*10^8 km, and the Earth travels around this obit in 365 days. The mass of the Earth is 5.97*10^24 kg.
(a) What is the magnitude of the orbital velocity of the Earth, in m/s?
(b) What is the radial acceleration of the earth toward the sun, in m/s²?
(c) What is the magnitude of centripetal force acting on the Earth?
(d) What is responsible for providing this centripetal force?
(e) Calculate the gravitational acceleration Of the Earth (not ON the Earth). Hint: think of your
answer to part (d), and set two forces equal to each other.
(f) What would happen to the Earth's motion if gravity was turned off? Answer as precisely as
possible.
Physics
GravitationDuring a solar eclipse, the Moon, the Earth, and the Sun all lie on the same line, with the Moon
between the Earth and the Sun. Calculate: (a) the net force on the Sun, (b) the net force on the Moon, and (c) the net force on the Earth. Hint: look up masses and distances!
Physics
GravitationAn astronaut weighing 214 lbs on Earth is on a mission to the Moon and Mars.
(a) What would he weigh in newtons when he is on the Moon? The acceleration due to gravity on the Moon is onesixth that on Earth.
(b) How much would he weigh in newtons when he is on Mars, where the acceleration due to gravity is 0.38 times that on Earth?
(c) What is his mass in kilograms on Earth?
(d) Which of the following are true? (Select all that apply.)
His mass on the Moon is greater than his mass on Earth.
His mass on the Moon is smaller than his mass on Earth.
His mass on Mars is exactly equal to his mass on Earth.
His mass on Mars is smaller than his mass on Earth.
His mass on Mars is greater than his mass on Earth.
His mass on the Moon is exactly equal to his mass on Earth.
Physics
GravitationA satellite of mass m is in a stable circular orbit around Earth at a distance R, from the center of Earth.
The mass of Earth is M...
(a) Derive an expression for the following in terms of m, R₁. M, and fundamental constants, as appropriate.
i. The orbital speed v₁ of the satellite
ii. The total energy of the satellite in this orbit, assuming gravitational potential energy to be zero at an
infinite distance from the center of Earth
Physics
GravitationTaking the radius of the earth to be 6400 km, by what percentage will the acceleration due to gravity at a height of 100 km from the surface of the earth differ from that on the surface of the earth?
(a) about 1.5%
(c) about 8%
(b) about 5%
(d) about 3%
Physics
GravitationA particle is projected vertically upwards and it reaches the maximum height H in T seconds. The
height of the particle at any time t will be :
(A) Hg(tT)²
(B) g(tT)²
(C) H1/2g(tT)²
(D) g/2(tT)²
Physics
GravitationTwo objects attract each other with a gravitational force of 16 units. If the distance between the two objects is doubled, explain what would happen. What is the new force of attraction between the two objects?
Physics
GravitationSuppose that a small communications satellite with mass mA is orbiting the Earth in a circular orbit. If we launch a second satellite B with twice the mass of A into circular orbit at the same orbital radius as satellite A, which of the following statements will be TRUE? Select ALL that apply:
Satellites A and B will experience the same local value of gravitational acceleration.
Satellites A and B will have the same orbital speed.
Satellites A and B will experience the same strength of gravitational force from the Earth.
Satellites A and B will have the same orbital period.
Physics
GravitationA shuttle moves between station A and B on earth along a vacuum tunnel which is a chord across the earth as shown. The shuttle moves on the bases of gravitational force only and the tunnel is frictionless. Find maximum speed attained by the shuttle. (g = 10 m/s²)
4 km/s
3 km/s
2 km/s
1 km/s
Physics
GravitationA piece of space debris is released from rest at an altitude that is two earth radii from the center of the earth. Compare the weight of the space debris in space at this point to its weight on earth.
Physics
GravitationA spaceship is stationary between a planet and its moon, experiencing an equal gravitational pull from each. When measurements are taken, it is determined that the craft is 300,000 km from the planet and 100,000 km from the moon.
What is the ratio of the mass of the planet to the mass of the moon?
What would be the ratio of their masses if the distance of the spaceship from the planet was R times the distance of the spaceship to the moon?
Physics
GravitationDetermine the force of gravity between the moon and a 5,500kg elephant. The mass of the moon is 7.35*10²² kg, and the distance between the elephant and the center of the moon is 1.737*10⁵ m.
Physics
GravitationThe value of the gravitational acceleration g decreases with elevation from 9.807 m/s² at the sea level to 9.767 m/s² at an altitude of 13000 m, where large passenger planes cruise. Determine the percentage reduction in the weight of an airplane cruising at 13000 m relative to its weight at sea level.
Physics
GravitationCompare the atmospheric circulation patterns of Venus and Earth. What are the roles of solar heating and planetary rotation? How does the presence of water on Earth give rise to weather that would be impossible on Venus? What is the effect on atmospheric circulation of the much larger mass of the Venusian atmosphere?
Physics
GravitationCompare and contrast Jupiter and Saturn. Indicate how their differing masses and distances from the Sun can explain many of the observed differences in the atmospheres and interiors of these two planets.
Physics
GravitationA Batman throws a gibber stone of weight 2500.0 N at an adversary. He applies a horizontal acceleration of 14.0 m/s². Find the magnitude of the horizontal force applied by the batman.
Choose an answer
A 3571.4 N
B 1785.7μN
C 1785.7 N
D 3571.43 mN
Physics
GravitationThe mass of the sun is about 2 x 1030 kg, and the mass of earth is 6 x 1024 kg. Approximately how many times greater is the mass of the sun than the mass of earth?
4 x 10 27 times greater
3 x 106 times greater
3 x 105 times greater
8 x 100 times greater
Physics
GravitationWhich statement best explains how the gravitational forces affect the mass and weight of an object on Earth and the Moon?
A. The weight of an object will be lighter while on the Moon, but the mass of an object will remain the same as on Earth and the Moon.
B. The mass and weight of an object will be lighter on the Moon compared to on Earth.
C. The mass of an object will be lighter while on the Moon, but the weight of an object will remain the same as on Earth and the Moon.
D. The mass and weight of an object will not be affected on the Moon compared to Earth,
Physics
GravitationJoe has a weight of 654 N (about 144 lb) when he is standing on the surface of the Earth.
(a) What would his weight (the gravitational force due to the Earth) be if he doubled his distance from the center of the Earth?
Physics
GravitationSuppose an astronaut has landed on Mars. Fully equipped, the astronaut has a mass of 123 kg, and when the astronaut gets on a scale, the reading is 454 N. What is the acceleration (in m/s2) due to gravity on Mars?
Physics
Gravitation11. If you are told that the accepted value of G is 6.67*1011 m³/ (s²kg), calculate the percent error, and make a statement concerning the accuracy of your results using the threshold of 10% for the percent error.
Physics
GravitationConsider a spherical homogeneous cloud of mass M made by an explosion. Due to energy received from the explosion, it is expanding and the expansion is spherically symmertric. At an instant its radius is R and all the particle on the surface are moving away from its center with velocity v₁. What would be its radius when expansion ceases (At every instant, density of cloud remain homogeneous)):
(1) GMR0/2GMR0BV0^2
(2) 2GMR0/2GMR0V0^2
(3) GMR0/2GM+R0V0^2
(4) None of these
Physics
Gravitation1. Two solid spheres of radius R made of the same type of steel are placed in contact, as shown in the figures above. The magnitude of the gravitational force that they exert on each other is F₁. When two other solid spheres of radius 3R made of this steel are placed in contact, what is the magnitude of the gravitational force that they exert on each other?
(A) F1
(B) 3F1
(C) 9F1
(D) 81F1
Physics
Gravitation2. An astronaut of mass 63 kg climbs a set of stairs with a total vertical rise of 3.4 m. (a) What is the astronaut's gravitational potential energy, relative to the bottom of the stairs, If the stairs are located on Earth? [2142 J] (b)Repeat (a) if the stairs are located on the Moon where g = 1.6 N/kg. [343 J]
Physics
GravitationBefore 2006, while Pluto was still considered a planet, people used this saying to remember the nine planet names: "My very excellent mother just sent us nine pizzas.”
Come up with a new sentence to help remember the eight planet names, in order.
Physics
GravitationA satellite of mass 500 kg orbits the earth with a period of 6,000 s. The earth has a mass of 5.97 x 1024 kg, a
radius of 6.38 × 106 m, and G = 6.67 × 1011 Nm²/kg2.
(a) Calculate the magnitude of the earth's gravitational force on the satellite.
(b) Determine the altitude of the satellite above the earth's surface.
Physics
GravitationNeptune has a slightly smaller radius and a slightly greater mass than Uranus. If you threw a ball with the same velocity on both planets, what would be true? (Assume both balls land back on the planet.)
A. The ball would travel farther on Neptune.
B. The ball would travel farther on Uranus.
C. The ball would travel the same distance on each planet.
D. Not enough information.
Physics
GravitationJohannes Kepler was a German mathematician and astronomer who lived from 15711630. He discovered the mathematical relationship between the orbital radius and orbital period:
This says:
The orbital period squared is proportional to the radius cubed.
Another way to write this is:
where k is the slope of a graph of T2 vs. 7³.
Let's see how well your data matches Kepler's prediction:
• make a calculated column that cubes the radius
• make another that squares the period
change the graph axes so the radius cubed is on the horizontal axis
• make period squared on the vertical axis
add a linear fit
What is the slope from the equation of the line on your graph?