The main requirement for a good conductor of electricity is to have a lot of valence electrons. Valence electrons are the electrons of the outer shells of atoms not bound with other atoms (for example through covalent bounds). These electrons are "free to escape" as soon as an electric field with enough intensity is applied to the material, and therefore these electrons will be free to move in the material producing an electric current.
When red light illuminates a grating with 7000 lines per centimeter, its second maximum is at 62.4°. What is the wavelength of this light?
ans: 633nm
Personally I feel that never trying is worse because at least when you fail you know what you need to improve on and that way you at least get some closure. Where as when you never try it you would never know whether or not you were able to do it
Answer: The forces acting on both of them will increase in magnitude.
Explanation:
According to Coulomb's law, the electrostatic force between two bodies is proportional to the product of their two charges. If the charge on A is increased this product increases in size (it must have been non-zero to begin with, since there was a force between them at first). Thus, the force between them rises.
A body of mass m has weight
F = GMm/r²
on the surface of the Earth, where G is the universal gravitational constant, M is the mass of the Earth, and r is it's radius.
If the weight is to be halved, then we have
1/2 F = 1/2 GMm/r² = (1/√2)² GMm/r² = GMm/(√2 r²)
so the distance between the body and the planet's center needs to be
√2 × 6.4 × 10⁶ m ≈ 9.1 × 10⁶ m