- #1
John Mcclane
- 1
- 0
hello sir ...can anyone explain me the value of (U) at infinity with respect to Earth as reference point
As the other answers implied, that isn't correct. Mgh is as typically used is a simplification for constant g. But for "escape", you'd combine with the equation for gravitational acceleration and integrate over the infinite distance to escape. That's how escape velocity is found and you can find the derivation on its wiki page.siddharth23 said:Potential energy is given by 'mgh' where the 'g' is acceleration due to the Earth's gravity. As soon as you escape the Earth's gravitational field, it stops affecting you. So the value of PE at infinity doesn't really come up.
Ya I realized that. Do I feel silly!russ_watters said:As the other answers implied, that isn't correct. Mgh is as typically used is a simplification for constant g. But for "escape", you'd combine with the equation for gravitational acceleration and integrate over the infinite distance to escape. That's how escape velocity is found and you can find the derivation on its wiki page.
And due to the continuous nature of the gravitational force equation, there is, of course, no distance where the force is exactly zero and Earth's gravity stops affecting you.
As others have pointed out, typically the potential energy is conventionally defined as U = 0 when the distance is infinity, r = ∞. Following this convention, U is negative for values of r < ∞. In other words, most of the time U is negative when an object is near Earth.John Mcclane said:hello sir ...can anyone explain me the value of (U) at infinity with respect to Earth as reference point
Absolute potential energy is the total amount of energy an object has based on its position and composition, without considering any external factors such as friction or air resistance.
Absolute potential energy is an intrinsic value that is unique to each object, while relative potential energy compares the energy of one object to another. For example, a ball on a shelf has a different absolute potential energy than a ball on the floor, but the relative potential energy between the two is the same.
The formula for absolute potential energy is E = mgh, where E is the energy in joules, m is the mass of the object in kilograms, g is the acceleration due to gravity (9.8 m/s²), and h is the height of the object in meters.
Yes, absolute potential energy can be negative if it is defined as the potential energy of an object in a reference point where the energy is zero. This can occur when the reference point is at a higher elevation than the object.
Absolute potential energy and kinetic energy are two forms of mechanical energy. As an object moves from a higher position to a lower position, it loses potential energy and gains kinetic energy. This relationship is described by the law of conservation of energy, which states that energy cannot be created or destroyed, only transferred between different forms.