Answer:
b)
Explanation:
If the charge is released at rest in an electric field, it will move along the electric field, going to regions of higher electric potential if it is a negative charge (against the field direction) and towards lower potential regions if it is positive (along the field). This means that the charge will gain kinetic energy, energy that only can come from a decrease in the electric potential energy.
For a positive charge: ΔEp = q*ΔV < 0 (as ΔV < 0)
For a negative charge: ΔEp = (-q) *ΔV < 0 (as ΔV > 0)
Answer:
The polar coordinate of 
is 
.
Explanation:
Given a point in rectangular form, that is 
, its polar form is defined by:
(1)
Where:
- Norm, measured in meters.
- Direction, measured in sexagesimal degrees.
The norm of the point is determined by Pythagorean Theorem:
(2)
And direction is calculated by following trigonometric relation:
(3)
If we know that 
and 
, then the components of coordinates in polar form is:
Since 
and 
, direction is located at 3rd Quadrant. Given that tangent function has a period of 180º, we find direction by using this formula:
The polar coordinate of is .
It’s D. An enlargement (hope this helps!)
Sorry I didn't see this before...
Okay, I see two major problems with this student's experiment:
1) Nitric acid Won't Dissolve in Methane
Nitric acid is what's called a mineral acid. That means it is inorganic (it doesn't contain carbon) and dissolves in water.
Methane is an organic molecule (it contains carbon). It literally cannot dissolve nitric acid. Here's why:
For nitric acid (HNO3) to dissolve into a solvent, that solvent must be polar. It must have a charge to pull the positively charged Hydrogen off of the Oxygen. Methane has no charge, since its carbon and hydrogens have nearly perfect covalent bonds. Thus it cannot dissolve nitric acid. There will be no solution. That leads to the next problem:
2) He's Not actually Measuring a Solution
He's picking up the pH of the pure nitric acid. Since it didn't dissolve, what's left isn't a solution—it's like mixing oil and water. He has groups of methane and groups of nitric acid. Since methane is perfectly neutral (neither acid nor base), the electronic instrument is only picking up the extremely acidic nitric acid. There's no point to what he's doing.
Does that help?
Answer:
Point A
Explanation:
The work done by stretching or compressing a spring is given by E=1/2kx²
The potential energy is numerically equal to the work done.
This means that the higher the bigger the value of the extension, x, the higher the energy contained.
In this scenario the modulus of x is considered.
Among the given values of x the modulus of -5 is the largest.
thus it gives the highest value of energy.
