A person lifting a chair is converting chemical energy to mechanical energy.
Answer:
E/4
Explanation:
The formula for electric field of a very large (essentially infinitely large) plane of charge is given by:
E = σ/(2ε₀)
Where;
E is the electric field
σ is the surface charge density
ε₀ is the electric constant.
Formula to calculate σ is;
σ = Q/A
Where;
Q is the total charge of the sheet
A is the sheet's area.
We are told the elastic sheet is a square with a side length as d, thus ;
A = d²
So;
σ = Q/d²
Putting Q/d² for σ in the electric field equation to obtain;
E = Q/(2ε₀d²)
Now, we can see that E is inversely proportional to the square of d i.e.
E ∝ 1/d²
The electric field at P has some magnitude E. We now double the side length of the sheet to 2L while keeping the same amount of charge Q distributed over the sheet.
From the relationship of E with d, the magnitude of electric field at P will now have a quarter of its original magnitude which is;
E_new = E/4
Answer: 9938.8 km
Explanation:
1 pound-force = 4.48 N
30.0 pounds-force = 134.4 N
The force of gravitation between Earth and object on the surface of is given by:

Where M is the mass of the Earth, m is the mass of the object, R (6371 km) is the radius of the Earth.
At height, h above the surface of the Earth, the weight of the object:

we need to find "h"
taking the ratio of two:

Hence, Pete would weigh 30 pounds at 9938.8 km above the surface of the Earth.
Answer:
Explanation:
An atom is constructed of three different particles known as electrons, protons and neutrons.
These particles have different mass and charges and are responsible for various characters than an atom posses.
An electron has a negative charge, a proton has positive charge and charge of neutron is neutral. Equal number of electrons and protons are present in an atom that make it electrically neutral but different conditions can occur if we remove these particles from an atom.
1 : Model of an ionized atom - an ionized atom is one which has some net charge on this. It can be either a positive charge or a negative charge.
If we need to sketch the model of an ionized atom then one should either keep the number of electrons less or proton.
2: Model of radioactive atom : A radioactive atom is one an unstable atom and has access of energy in its center. It can be caused by adding either neutrons or protons.