Gravitational force Definition and 491 Threads

Homework Statement Two identical spheres weighing at 100kg are suspended from massless cables at a length of 100m. The top of the cables are separated at exactly 1m apart. What is the distance from the centers of the spheres? The attempt at a solution I tried using equilibrium to solve for...

A infinitely long rod, A, with linear mass density, say p, is placed along the z-axis. Another thin rod, B, of length L and mass density, say p_{2}, is placed orthogonally to A on the x-axis from x=a to x=a+L. What is the gravitational force experienced by rod B from rod A? I have solved a...

Homework Statement Two objects attract each other gravitationally with a force of 2.7 10-10 N when they are 0.25 m apart. Their total mass is 4.0 kg. Find their individual masses. larger mass - I kind of guessed this was 4.0 kg but don't know how to do it. smaller mass ? kg The...

1. Homework Statement Four 9.0 kg spheres are located at the corners of a square of side 0.72 m. Calculate the magnitude of the gravitational force on one sphere due to the other three. 2. Homework Equations Fg=G(M1)(M2)/r^2 3. The Attempt at a Solution I figured out the...

Homework Statement A student of mass 72 kg is at an altitude of 1.5 km falling towards the Earth's surface, accelerating at 9.8 m/s2. What is the acceleration of the Earth as it falls toward the student? The radius of the Earth is 6.38 x 10^6 m. Homework Equations The Attempt at a...

My appologies for such a lame question, but it has been near 50 years since physics in college, and not much use since. A friend helped another to pick up a very large and heavy door. As the second person was taller than he, he was under the impression that he had the "heavy' end of the door...

Homework Statement M1 is a spherical mass (43.0 kg) at the origin. M2 is also a spherical mass (11.8 kg) and is located on the x-axis at x = 52.8 m. At what value of x would a third mass with a 16.0 kg mass experience no net gravitational force due to M1 and M2? Homework Equations...

Hi, I'm having trouble understanding this concept. A refrigerator is on a ramp of length d and it is being pushed up the ramp. What is the work done by the gravitational force? In the book it says mgdcos180 which is -mgd. I thought that the horizontal component of gravity was mgsin(theta) so...

Homework Statement It is known that the electric force of repulsion between two protons is much stronger than their gravitational attraction. For two protons a distance R apart, calculate the ratio of the magnitude of the repulsion to that of the attraction. Homework Equations...

Bonjour, We can see light emitted by a star which is effectively behind a gravitational mass. Ok! The light path will curve. Or the light path will be as straight as the space surrounding the gravitational mass. Ok! My question is: When two parallel beams are emitted in the same parallel...

I feel sort of confused with some concepts. Does Gravity mean gravitational force? Is that every object has different gravitational force according to their mass? So what is 9.81m/s^2? This is not gravity as i thought before, isn't it? THis is only the acceleration due to gravity? SO gravity is...

Homework Statement Earth exerts a downward gravitational force of 8.9 N on a cake that is resting on a plate. The plate exerts a force of 11.0 N upward on the cake. [ add the rest of the problem: and a knife exerts a downward force of 2.1 N on the cake. Draw a free-body diagram of the cake.]...

Homework Statement There exists a distance x between the Earth and the moon where the net gravitational force acting on an arbitrary particle of mass m is zero. Assuming only earth-moon interaction, show the distance is given by: Homework Equations x = dem/(sqrt(Mm/Me) + 1) where...

Homework Statement If the force of gravity(weight) of a 1.2kg textbook were to be measured at various distances (d) from the Earth's center, the data would appear as follows: Force(weight)[kg*m^2/s^2] 1) 11.8 2) 5.21 3) 1.9 4) 1.0 Distance[m] 1) 6.4 x 10^6 2) 9.6 x 10^6 3) 16 x 10^6 4) 22 x...

The question: assuming that the moon circles the Earth in an orbit of radius d show thatthe periodic time T of the moon may be expressed as: T=2pi d sqrt d/r sqrt g where r is the radius of Earth and g is acceleration due to gravity on Earth's surface i took up physics 2 to 3 months ago on...

I'm going nuts trying to figure this out... in textbooks and online, everything i read says that the moon and Earth have a much stronger gravitational force between them than the sun and the earth, and this is why the moon has greater effect on tides than the sun. They all say that this is...

If F=GmM / d^2 Let's assume we're using it to measure the force between me and the earth, as i go further away the force on my decreases, what would happen if i could go right to the centre of the earth? would i be crushed under the force or what?

1. Homework Statement Three uniform spheres are located at the corners of an equilateral triangle. Each side of the triangle has a length of 3.80 m. Two of the spheres have a mass of 3.30 kg each. The third sphere (mass unknown) is released from rest. Considering only the gravitational...

Homework Statement Three uniform spheres are located at the corners of an equilateral triangle. Each side of the triangle has a length of 3.80 m. Two of the spheres have a mass of 3.30 kg each. The third sphere (mass unknown) is released from rest. Considering only the gravitational forces...

Homework Statement Suppose the Earth is a perfect sphere with R=6370 km. If a person weighs exactly 600.0N at the north pole, how much will the person weigh at the equator? (Hint: the upward push of the scale on the person is what the scale will read and is what we are calling the weight in...

Homework Statement A bowling ball (mass = 7.2 kg, radius = 0.13 m) and a billiard ball (mass = 0.40 kg, radius = 0.028 m) may each be treated as uniform spheres. What is the magnitude of the maximum gravitational force that each can exert on the other?Homework Equations F = G(m1m2/r^2)The...

Okay, this was just a curious question that's been bobbing around in my head recently. The formula for gravitational force between two masses is F_{g} = G \frac{m_{1}m_{2}}{r^2} right? So, gravitational force increases as you approach the center of the earth. I was wondering, what is the...

Use the fact that the gravitational attraction between particles of mass mi and m2 at a distance r apart is Gm1m2/r^2. Slice the object into pieces, use this formula for the pieces, and sum using a definite integral What is the force of gravitational attraction between a thin uniform rod of...

Three particles far away from any other objects are located on a straight line. The masses of these particles are ma = 363kb, mb= 517 kg, and mc = 154kg. Find the magnitude and direction of the net graviational force actiong on particle a, particle b, and particle c. The distance between a and b...

Homework Statement A hydrogen atom is composed of a nucleus containing a single proton, about which a single electron orbits. The electric force between the two particles is about 2.3 x 10^39 times greater than the gravitational force. Suppose we could change the distance between the proton...

An unmanned spacecraft is in a circular orbit around the moon, observing the lunar surface from an altitude of 43.0 km (see Appendix F). To the dismay of scientists on earth, an electrical fault causes an on-board thruster to fire, decreasing the speed of the spacecraft by 20.0 m/s. If...

If the gravitational force between two massive bodies were measured and divided by the product of their masses, and then multiplied by the square of the distance between their centers of mass, what number would result? is it 9.8N?

I don't know if this is a very easy question or if I am totally missing something but the question is: What is the magnitude and direction of the gravitational force that acts on a women who weighs 500 N at the surface of the earth? From reading this, I am thinking that the magnitude would...

What is the magnitude of the net gravitational force on the 20.0 kg mass? What is the direction of the net gravitational force on the 20.0 kg mass? What is the magnitude of the net gravitational force on the 5.0 kg mass? I'm completely lost on this.

A uniform rod of mass M = 20kg and length L = 5m is bent into a semicircle. What is the gravitational force exerted by the rod on a point mass m = 0.1 kg located at the center of curvature of the circular arc?

If Earth attracts the Moon with gravitational force, then according to 3,rd Newton's law the Moon attracts the Earth with the same but opposite force. But what if someone argues that the Moon attracts the Earth anyway due to its own gravitation, can we really say that it's the reaction force...

OK, I'm having trouble with this and can't seem to find an explanation for it. So To start off, i understand gravitational force, which is always just m*g (mass * -9.8 m/s). Now, when an object is moved by a force either horizontally or up an incline, etc. how do you figure out the work done...

The question i am stumped on is as follows The mass of the moon is 7.35 x 10^22 kg. At some point between Earth and the moon, the force of Earth's gravitational attraction on an object is canceled out b the moons force of gravitational attraction. If the distance between Earth and the moon...

Objects with masses of 285 kg and a 585 kg are separated by 0.390 m. Find the net gravitational force exerted by these objects on a 30.0 kg object placed midway between them. Then, at what position (other than infinitely remote ones) can the 30.0 kg object be placed so as to experience a net...

If you jumped out a plane, you would begin speeding up as you fall downward. Eventually, due to wind resistance, your velocity would become constant with time. After this occurs, the wind resistance force’s magnitude is a.much smaller that the gravitational force acting on you. b.slightly...

Hi, I attached a diagram... to find out the arrangement of the magnitude of the net gravitational force on the particle labeled m from the smallest to the biggest. my answer is A B D C, anyone had a different way of looking at it? could you explain? some of my friends said it was A D B...

this proplem has been giving me a lot of trouble. I was wondering if anyone could lead me in the right direction. You drop a 2.00 kg textbook to a friend who stands on the ground at distance D = 10.0 m below. Your friend's outstretched hands are at distance d = 1.50 m above the ground...

I would appreciate any help on this problem: In Fig. 14-18a, a square of edge length .232m is formed by four spheres of masses m1 = .00372 kg, m2 = .00958 kg, m3 = .00408 kg, and m4 = .00835 kg. In unit-vector notation, what is the net gravitational force from them on a central sphere with...

Sir, Two point masses each equal to 1 kg attract one another with a force of 1 kg.wt. What is the distance between the 2 point masses? I solved it in the following way: Here F = 1 kg.wt = 9.8 Newton, m1 = m2 = 1 kg, G = 6.6 x 10^(-11) N.m^2/kg^2 F = [G(m1)(m2)]/r^2 r^2 = [G(m1)(m2)]/F...

I am supposed to balance the coulomb repulsive and gravitational force in a way that both forces between the Earth and the moon have the same amount. For that I can just use F_C = F_G 1/(4\pi\epsilon_0) * (Q_1*Q_2)/(r^2) = f (m_1 * m_2)/r^2 and then put Q_1*Q_2 on one side. Now I have...

Two identical balls of mass 38 g are suspended from threads of length 1.5 m and carry equal charges of 16 nC as shown in the figure. Assume that θ is so small that its tangent can be replaced by its sine and find the value of x. (picture attached) I know that the sum of all the forces must...

Hi, I posted this question a while back on these forums. Didn't get an answer though. How long will it take for two identical masses to reach each other by their attractive gravitational force? Their masses can be 1kg and the distance between them 1m to simplify it. Do NOT assume that the...

For the equation: U=\frac{-GMm}{h} Where h is the distance between the center of masses M and m. In Calculus, they teach you derivatives. The derivative of U with respect to h is: dU=d\left(\frac{-GMm}{h}\right) dU=\frac{GMm}{h^2} Which is the gravitational force. Were I to apply this...

Hello all..I need some help on these 2 questions..:rolleyes: Thanx -A bowling ball (mass = 7.2 kg, radius = 0.15 m) and a billiard ball (mass = 0.47 kg, radius = 0.028 m) may each be treated as uniform spheres. What is the magnitude of the maximum gravitational force that each can exert...

What does it mean if between an electron and a proton has negative gravitational force? Does this make the force attractive or repulsive?

A student stands on a bathroom scale in an elevator at rest on the 64th floor of a building. The scale reads 836 N. a) As the elevator moves up, the scale reading increases to 935 N, then decreases back to 836 N. Find the acceleration of the elevator. b) As the elevator approaches the 74th...

At a distance H above the surface of a plane, the true weight of a remote probe is one percent less than its true weight on the surface. The radius of the planet is R. Find the ratio H/R. Work: Let Mp be mass of planet and Ms be the mass of space probe (true weight) Ft = GMpM/(r+h)^2...

Hi there, everybody, ivgot a question here, In a distant solar system, a planet (mass 4.13x1028 kg) is orbiting the sun (mass 7.67x1030 kg) with an orbit radius of 2.72x1011 m. Calculate the magnitude of the net gravitational field strength midway between the planet and the sun, in N kg -1...

See Attached Word Document :smile:

The problem says to find the point between Mars and the Sun at which an object can be placed so that the net gravitational force exerted by Mars and the Sun on that object is zero. Here is what I've done so far, but I'm not getting the correct answer: F(sun) = F(mars)...