# Calculus

Okay so I have the following question and I am totally stuck:

Newton's Law of Gravitation says that the magnitude F or the force exerted by a body of mass m on a body of mass M given by
F=(GmM)/r^2
where G is the gravitational constant and r the distance between the bodies. A cosmonaut insde a spaceship is approahing a newly disvoered Planet Htrea. Looking at his instruments, he notices that at a distance of 20000km from the planet, its gravitational pull is increasing at 1N/km as he approaches the planet. Compute the gravitational force that the planet will exert on the spaceship at a distance of 10000km from it.

I don't see how I can do this without the mass of the plants or anything, theres to many variables. I don't know, in great need of help, please.

A note on distances: The distance in the law of gravitation is distance to the center of mass, normally the geometric center of the body.

F=(GmM)/r^2 Let M be the new Planet.

F/M= Gm/r^2 This quantity is called gravitational field, in N/kg units.

The gravitation field is dependent on distance squared from the center of the planet. So at half the distance, it ought to be four times as great. Think that out. You can get the new gravitational pull from that, in N/kg.

Now you are correct, the actual force will require the mass of the space ship.
Force= g * massspaceship where g is the field value of gravitational pull, in N/kg

Wow I am still totally lost. At half the distance it will be 4 times as great, this means that the new gravitational pull will be 4N/kg?

But I still don't know how that will let me find the gravitational force on the spaceship if we don't have the mass of the spaceship. I was thinking filling in the equation based on the first information given and find the mass, but I don't think I'm sure we have all the numbers, so that still wouldnt work. G=1N/km, m=?, M=? r=20000km. So it still can't work..

Yes, at half the distance..

g= 1N/kg (2E7/r )^2 so as r becomes 1E7, then g is 4N/kg.

You cant get the Force without the mass of the spaceship.

F=ma= mg you have to have m.

Okay that's what I was thinking and what was confusing me, but I thought maybe there was a way around that since they didn't give us one. Thanks = )

Well actually,what that guy got is wrong.The answer would e the recipicol of that.By the way Hello,I'm Keira.

Hello Keira.
I still can't get the answer from that though can I?

1. 👍
2. 👎
3. 👁

## Similar Questions

1. ### History

Which accurately describes Newton’s Laws? newton defined the three laws of motion that govern planetary bodies and objects on earth newton defined three laws of thermodynamics that predict the conservation of energy newton

2. ### Science check answer quick!

I really do not understand Number 7 Which of these does Newton's law of universal gravitation imply? (Points : 1) The force of gravity between two objects is inversely proportional to the product of the two masses.

3. ### 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

4. ### english

Which label best fits the following text? Sir Isaac Newton, the first person who studied gravity seriously, discovered what is known as the law of universal gravitation. It defines the amount of attraction of one particle of

1. ### SCIENCE

1. How does mass and acceleration affect force? (What happens to force if mass increases? What happens to force if acceleration increases? ) 2. What is the equation for Newton’s 2nd Law of motion? 3. How do you calculate mass

2. ### Physics

Which law gives the force between two objects that is related to their mass and distance? Kepler's law Coulomb's law Newton's second law of motion Newton's law of gravitation*****

3. ### Physics (Newton's and Coulomb's Laws) **ASAP**

1. Which law gives the force between two objects that is related to their mass and distance? A. Newton's law of gravitation B. Coulomb's law C. Kepler's law D. Newton's second law of motion 2. What is the property that allows a

4. ### Physics !!!ASAP!!!

1. Which law gives the force between two objects that is related to their mass and distance? A. Newton's law of gravitation B. Coulomb's law C. Kepler's law D. Newton's second law of motion 2. What is the property that allows a

1. ### 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.

2. ### Physics (Conservation of momentum)

1. Which of Newton’s laws of motion states that an object at rest stays at rest and an object in motion stays in motion with the same speed and the same direction unless acted upon by an unbalanced force? A. Newton's Third Law

3. ### Physics

Select as many of the following statements that are TRUE when comparing Coulomb's Law to Newton's Universal Law of Gravitation. * Both Laws are about the relationship between two masses. Both Laws are "inverse square"

4. ### science

15. Rowing a boat and a rocket taking off into space are examples of which law of motion? * A law of gravitational force*** B law of inertia C Newton's 2nd law of Motion D Newton's 3rd law of motion