C. zinc is best used for making screws. Zinc is best used for making alloys, anything made from 55% or 95% copper more then likely contain zinc
Use Coulomb law: F = k * q1*q2 / (r^2), where k = 9.00 * 10^9 N.m^2/C^2
F = 9.00 * 10^9 N.m^2/C^2 * 2.4*10^-8 C * 1.8*10^-6 C / [0.008m]^2 = 38.88 * 10^ -5 N
F = 39 * 10 -5N
The electric field due to a point charge of 20uC at a distance of 1 meter away from it is 180000
.
First, you have to know that the space surrounding a load suffers some kind of disturbance, since a load located in that space will suffer a force. The disturbance that this charge creates around it is called an electric field.
In other words, an electric field exists in a certain region of space if, when introducing a charge called witness charge or test charge, it undergoes the action of an electric force.
The electric field E created by the point charge q at any point P, located at a distance r, is defined as:

where K is the constant of Coulomb's law.
In this case, you know:
- K= 9×10⁹

- q= 20 uC=20×10⁻⁶ C
- r= 1 m
Replacing in the definition of electric field:

Solving:
<u><em>E=180000 </em></u>
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Finally, the electric field due to a point charge of 20uC at a distance of 1 meter away from it is 180000
.
Learn more:
The material that is more closely related to the Styrofoam insulator.
Styrofoam is the term that is used for polystyrene foam in a trademark form. It is a petroleum-based plastic.
Keeping something warm includes the stopping of the transfer of heat from one object to another. This is how insulation works.
Styrofoam is an insulator, which means it'll help keep the heat from the environment out of your cooler. However, you'll still need cooling agents (like ice packs) to make the cooler cold in the first place.
Styrofoam is usually made mostly of air, which means it is a poor conductor of heat, but an excellent convector. It traps the air in small pockets, which blocks the flow of heat energy. This reduces both conduction and convection and makes Styrofoam a good insulator.
To learn more about Styrofoam here
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Answer:

Explanation:
Absolute zero in the Kelvin scale = -273.15 °C
Temperature difference in the boiling and freezing point

Change in 21.5°C = Change of 100°C in M

Difference in the Celsius scale

Change in
corresponds to

Therefore the absolute zero in the Methane scale is
