Tuesday, 4 August 2020, 4:25 PM
Site: The Science Portal: 21C Science with Style
Course: The Science Portal: 21C Science with Style (21CScience)
Glossary: IB Physics Glossary
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Ohm's law states that current is proportional to voltage, at constant temperature, $$I \prop V$$. (d) The graph should be a straight line passing through the origin. For nonohmic conductors current is not proportional to voltage, $$I \cancel{ \prop} V$$. The graph is nonlinear. Examples of nonOhmic conductors include
as $$I \uparrow, T \uparrow, R \uparro \Rightarrow$$ gradient is not constant, or, as $$I \downarrow, T \downarrow, R \downarrow \Rightarrow$$ gradient is not constant.
Typical graphs can be yaxis: I, xaxis: V, $$R \uparrow \Rightarrow \frac{V}{I} \uparrow \Rightarrow$$ gradient decreases;
yaxis: V, xaxis: I, $$R \uparrow \Rightarrow \frac{V}{I} \uparrow \Rightarrow$$ gradient increases.
NTC (negative temperaure coefficient): $$T \uparrow \downarrow R \downarrow \uparrow$$;
PTC (positive temperature coefficent): $$T \uparrow \downarrow R \uparrow \downarrow$$.
brightness $$\uparrow \downarrow$$, $$ R \downarrow \uparrow$$;
a variation in strain of a material (deformation per unit length due to the effect of an applied load/mass) produces a variation in electrical resistance of material

One Mole of substance has as many molecules as there are atoms in 12g of Carbon12. (d) 
OppenheimerVolkoff limit is approximately 23 solar masses for mass of core for Super Red Giant; for core masses < 23 solar masses (above 1.4 solar masses) $$\rightarrow$$ Neutron star for core masses > 23 solar masses $$\rightarrow$$ Black hole. 
Optically activesubstances rotate the plane of polarization of the incident light. The amount of rotation may depend on the concentration of the substance/solution and the amount/length/thickness. 
Orbital Motionoccurs when the gravitation provides the centripetal force for circular orbital motion: $$F = G \frac{Mm}{r^2}=\frac{mv^2}{r}$$. 