check my understanding please.
Larry weighs 300 N at the surface of the earth. what is the weight of the earth in the gravitational field of Larry?
-would it still be 300 N
an astronaugt lands on a planet that has twice the mass as earth and twice the diameter. how does the astronaut weight differ from that on earth?
-his weight on earth would be less
if the moon pulls the earth as strongly as the earth pulls the moon, why doesnt the earth rotate around the moon, or why don't both rotate around a point midway between them?
-is it because they are in orbit and have a foce field
2) Isn't gravity force= GMm/d^2
3) Where is the center of mass for Earth/Moon. ISn't the center of mass what they both rotate around?
Let's go through each of your statements and check your understanding:
1. Larry weighs 300 N at the surface of the earth. What is the weight of the earth in the gravitational field of Larry? - Would it still be 300 N?
To find the weight of the earth in the gravitational field of Larry, we need to apply Newton's law of universal gravitation, which states that the force between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. In this case, Larry's weight is the force exerted by the earth on him, which is equal to 300 N.
However, the weight of the earth in the gravitational field of Larry would not be 300 N. While Larry exerts a gravitational force on the earth, it is extremely small compared to the mass of the earth, so the resulting force is negligible.
2. An astronaut lands on a planet that has twice the mass as the earth and twice the diameter. How does the astronaut's weight differ from that on earth? - His weight on earth would be less.
The weight of an object on a planet depends on the gravitational pull of that planet. The force of gravity is directly proportional to the mass of the planet. In this case, the planet has twice the mass compared to Earth.
Since the weight of an object is the force of gravity acting on it, the astronaut's weight on this new planet would be greater than on Earth. With a planet twice the mass of Earth, the gravitational force exerted on the astronaut would also be twice as strong, resulting in an increased weight for the astronaut.
3. If the moon pulls the earth as strongly as the earth pulls the moon, why doesn't the earth rotate around the moon, or why don't both rotate around a point midway between them? - Is it because they are in orbit and have a force field?
The reason the earth doesn't rotate around the moon or both objects rotate around a point midway between them is because they are in orbit. When an object is in orbit, it is moving in a curved path around another object due to the gravitational force between them.
In the case of the earth and the moon, they are mutually attracted to each other due to their masses. This mutual gravitational attraction creates a force that causes them to orbit around a common center of mass, known as the barycenter. However, the barycenter is not exactly at the center of the earth or the moon since the mass of the earth is much larger compared to the moon. As a result, the earth exerts a greater gravitational force on the moon, causing the moon to orbit around the earth.