8.38e -21Q^2 -1.07e -23Q^2 +3.15e +19
= 10.46e -44Q^2 + 19
44Q^2 = 10.46e + 19
Q^2 = 523/2200e + 19/44
Q1= ≈ -1.03828
Q2= ≈ 1.03828
"A machine can decrease either the input force or the input distance needed to do a given amount of work" is the best statement that describes why a machine is useful.
Answer: Option D
<u>Explanation
:</u>
A machine is simply defined as a device that helps humans, helping them to transfer the required amount of force to compete any task, changing the direction of motion, increasing the magnitude of force to complete any task, reduce the time or distance needed to cover while performing any task.
Machines can be simple mechanical device or a combination of multiple mechanical or technical devices to reduce the amount of input force or increase the output.
Can you provide a picture
Put simply, a covalent bond is a chemical bond between two atoms where electron pairs are shared.
<span>The number of protons in every atom of an element determines the atomic number of an atom. Short after Rutherford made the gold foil experiment, the British scientist Henry Mosely discovered that the atoms of every element have a unique positive charge in their nuclei. This positive charge is the number of protons and is called atomic number. So, the atomic number identifies every different element.</span>