What do u, F and V represent in physical head and neck? It's the lens in physics of grade two. It's like the distance between the lens and the object

What do u, F and V represent in physical head and neck? It's the lens in physics of grade two. It's like the distance between the lens and the object

U object distance: the distance from the object to the lens
F focal length: the distance from the focal point of the lens to the optical center
V image distance: the distance from the image to the lens

The experiment shows that the gravity of an object is directly proportional to its mass, which is expressed by the formula g = mg, that is, the greater the mass, the greater the gravity
So, is the mass of an object with zero gravity zero?

In other words, if G ≠ mg, it can not be said that the mass of the object with 0 gravity is 0

Why does Einstein say that when the speed of light is equal to the time of some objects, it will stop?

The basic assumption, called relativity, is that no matter how fast the observer moves freely, the laws of science should be the same for them. This is certainly true for Newton's laws of motion, but now the idea has been extended to include Maxwell's theory and the speed of light: no matter how fast the observer moves, the speed of light is the same, Perhaps the most famous is the equivalence of mass and energy, which can be expressed by Einstein's famous equation E = MC ＾ 2 (where e is energy, M is mass, C is the speed of light), and the law that nothing can move faster than light, In other words, it will be more difficult to accelerate it. This effect only has practical significance when the object moves at a speed close to the speed of light. For example, the mass of an object moving at 10% of the speed of light is only 0.5% higher than that of the original, while the mass of an object moving at 90% of the speed of light is only 0.5% higher than that of the original, When an object approaches the speed of light, its mass rises faster and faster, and it needs more and more energy to accelerate further. In fact, it can never reach the speed of light, because then the mass will become infinite. According to the principle of mass energy equivalence, it needs infinite energy, Relativity restricts any normal object to always move at a speed lower than that of light. Only light or other waves without intrinsic mass can move at the speed of light
An equally remarkable achievement of relativity is that it has changed our concepts of space and time, On the other hand, in the theory of relativity, all observers have to agree on how fast light moves, They can't agree on how far light travels, so now they don't agree on how much time light takes. (in any case, the time light takes is the speed of light - which is consistent with all observers - to remove the distance light travels - which is inconsistent with them.), Relativity ends the concept of absolute time! In this way, each observer has his own clock to measure time, and the readings of the same clock carried by different observers need not be consistent

Why can the formula of gravity be written as: g = mg, w = mg, and P = mg

Because P = g / g = mg. M is mass. G is gravity. G = 9.8n/kg. G is uniform

What does e = MC2 mean?

In Einstein's theory of relativity, the relation between mass and energy is involved. E is equal to the square of the object's mass and the speed of light

As for the formula g = mg, the following misunderstandings are
A gravity is G times the mass B G is the ratio of gravity to mass C at the same place G is the fixed value d the gravity of an object is proportional to its mass
Please explain. Thank you

A wrong, gravity and mass are different physical quantities, not simple multiple relations
The others are right

What do e, C, m of E = MC2 mean?

M is the mass and C is the speed of light

Find the buoyancy pressure difference, f =?
It's urgent. I can't do science problems,

F = ρ GV row