An independent variable is a variable that does not depend on anything. It is manipulated to determine the value of a dependent variable<span>. The dependent variable is what is being measured in an experiment or evaluated in a mathematical equation and the independent variables are the inputs to that measurement. Example: Time would always be an independent variable because nothing affects time, however, time can affect everything. </span>
Answer: Friction also prevents an object from starting to move, such as a shoe placed on a ramp. When friction acts between two surfaces that are moving over each other, some kinetic energy is transformed into heat energy. Friction can sometimes be useful.
Explanation:
The valence electrons of metals are weakly attracted to the parent nuclei, so the electrons break free and float. The moving electrons form a electron <u>negative</u> blanket that binds the atomic <u>positive</u> nuclei together, forming a metallic bond.
So the answers are <u>{ Negative }</u> and <u>{ Positive }.</u>
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