Answer:d
Explanation:
Drift velocity is given by
where 
=drift velocity
I=Current
n=no of electron
Q=charge of Electron
A=cross-section
If area of cross-section decreases gradually then drift velocity will increase because drift velocity is inversely proportional to Area of cross-section
Answer:
<em>b. Observe the radio waves coming from all dark matter; from the strength of the radio waves from each cluster, estimate the amount of dark matter needed to produce them.</em>
<em></em>
Explanation:
The universe is thought to be made up of 85% dark matters. <em>Dark matter is called dark because it does not appear to interact with the electromagnetic field, which means it doesn't absorb, reflect or emit electromagnetic radiation, and is therefore difficult to detect. This means that option b is wrong since radio wave is an electromagnetic wave</em>. Dark matter is a form of matter that makes up about a quarter of the total mass–energy density of the universe. Dark matter was theorized due a variety of astrophysical observations and gravitational effects that cannot be explained by accepted theories of gravity unless there were more matter in the universe than can be seen.
Answer: Both of the compounds contain primary bonding; however, the bonding is of different types. Magnesium chloride (MgCl₂) contains ionic bonds, which are stronger and involve the complete transfer of electrons. Meanwhile, ethane (C₂H₆) also bonds by electron transfer but the electrons are not completely transferred from one atom to another. Instead, they are shared, forming what is known as a covalent bond.
Is balancing .
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