Scaling factor of Energy in a capacitor with change in charge

If we substitute Q/V for C, we get:E = \frac{1}{2}\left(\frac{Q}{V}\right)V^2 = \frac{1}{2}QV So our original equation for energy, E = \frac{1}{2}QV, is also consistent with the equation E = \frac{1}{2}CV^2. This confirms that your logic and method are correct.
  • #1
mrcotton
120
0

Homework Statement


AQA Section A Q18 Jun 11
photbucket3_zps580de911.jpg


Homework Equations



The answer should be C

E=.5QV and C=Q/V

The Attempt at a Solution



So the original Q has increased by 1.5 times If C is constant than the voltage must also increase by 1.5 times

Now the energy E is E=.5QV V has increase by 1.5 and and so has Q which is 2.25

Infact in typing this out I think I just solved it. Is this logic and method ok
 
Physics news on Phys.org
  • #2
mrcotton said:

Homework Statement


AQA Section A Q18 Jun 11
photbucket3_zps580de911.jpg


Homework Equations



The answer should be C

E=.5QV and C=Q/V

The Attempt at a Solution



So the original Q has increased by 1.5 times If C is constant than the voltage must also increase by 1.5 times

Now the energy E is E=.5QV V has increase by 1.5 and and so has Q which is 2.25

Infact in typing this out I think I just solved it. Is this logic and method ok

Seems fine to me.
 
  • #3
Yup. You may recall that the energy stored in a capacitor is also given by:


[itex] E = \frac{1}{2}CV^2[/itex]
 

FAQ: Scaling factor of Energy in a capacitor with change in charge

What is the scaling factor of energy in a capacitor with change in charge?

The scaling factor of energy in a capacitor with change in charge is known as the capacitance. It is a measure of the amount of charge that a capacitor can store per unit of voltage.

How does the scaling factor of energy in a capacitor change with an increase in charge?

As the charge on a capacitor increases, the capacitance also increases. This means that the capacitor can store more energy for a given voltage. The relationship between charge and capacitance is directly proportional.

What is the formula for calculating the scaling factor of energy in a capacitor with change in charge?

The formula for capacitance is C = Q/V, where C is capacitance, Q is charge, and V is voltage. This formula can be rearranged to find the scaling factor of energy, as C = Q/V = E/V, where E is energy.

How does the distance between the capacitor plates affect the scaling factor of energy?

The distance between the capacitor plates, also known as the separation, has an inverse relationship with the capacitance. This means that as the distance between the plates increases, the capacitance decreases, and vice versa. This relationship is described by the formula C = εA/d, where ε is the permittivity of the material between the plates, A is the area of the plates, and d is the separation.

Can the scaling factor of energy in a capacitor be changed by altering the material between the plates?

Yes, the scaling factor of energy can be changed by altering the material between the plates. The permittivity of the material is a key factor in determining the capacitance. Materials with a higher permittivity, such as dielectrics, can increase the capacitance and therefore the scaling factor of energy in a capacitor with change in charge.

Back
Top