Answer:
Mg- 27 means isotope with 12 protons and 15 neutrons.
Also 27 is mass number which express sum of protons and neutrons.
In nucleus one neutrn decays to electron and proton. Mass number remain same but Al-27 nucleus contain 13 protons and 14 neutrons. Electron is ejected out from nucleus.
Current= voltage divided by resistance
120/30=4
The force of friction is that force that tends to oppose the motion of the body with the surface in contact... are you clear with it?
Answer:

Explanation:
The equations of equilibrium for the child are: (x' in the direction parallel to slope, y' in the direction perpendicular to slope)

After some algebraic manipulation, an expression for the coefficient of kinetic friction is obtained:






Free insulative sheets and insulative sheets backed by a grounded conductor are the only cases in which it is possible to extract reliable information from a noncontacting measurement of the charged state of an insulator. In both cases, the electric field from the charge is the deciding factor.<span>
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