The only statement on the options that says true about density is:
> The density of an object determines whether it will sink or float.
Why?
Density is a physical property of an object.
Density is not derived as a unit of measure. It is derived from 2 fundamental units: kg and m.
The Density of an object is not constant.
Density is calculated by dividing the mass by the volume of an object.
Answer:
Amplitude and Frequency
Explanation:
Analog signals are composed of continuous waves that can have any values for frequency and amplitude. These waves are smooth and curved.
Radio transmissions are a combination of two kinds of waves: audio frequency waves that represent the sounds being transmitted and radio frequency waves that "carry" the audio information. All waves have a wavelength, an amplitude and a frequency as shown in the figure. These properties of the wave allow it to be modified to carry sound information.
The two most common types of modulation used in radio are amplitude modulation (AM) and frequency modulation (FM). Frequency modulation minimizes noise and provides greater fidelity than amplitude modulation, which is the older method of broadcasting . Both AM and FM are analog transmission systems, that is, they process sounds into continuously varying patterns of electrical signals which resemble sound waves.
Answer:
Explanation:
#2 and for 2 i think that its the first one which says that there have to be a potential difference
#3 the answer is not at all
geologists use radiometric dating to estimate how long ago rocks formed, and to infer the ages of fossils contained within those rocks. the methods work because radioactive elements are unstable, and they are always trying to move to a more stable state. so, they do this by giving off radiation. this process by which an unstable atomic nucleus loses energy by releasing radiation is called radioactive decay. the thing that makes this decay process so valuable for determining the age of an object is that each radioactive isotope decays at its own fixed rate, which is expressed in terms of its half-life. so, if you know the radioactive isotope found in a substance and the isotope's half-life, you can calculate the age of the substance.
From Ohm's law: R = V / I
Resistance = (voltage) / (current)
The first paragraph TELLS you that the current is always 0.5 A, and the table tells you the voltage across each piece of wire.
Again . . . <em>R = V / I</em>