# Electrons- conservation of energy - electric potential

• mussgo
In summary, the conversation discusses the problem of an electron being projected towards a fixed proton with an initial speed of 2.4 x10^5 m/s and determining at what distance from the proton the electron's speed will be twice its initial value. The solution involves finding the total energy of the system, which is a constant, and using it to find the distance at which the total energy will be balanced when the electron's speed is doubled.
mussgo
An Electron is Projected An electron is projected with an initial speed of 2.4 x10^5 m/s directly toward a proton that is fixed in place. If the electron is initially a great distance from the proton, at what distance from the proton is the speed of the electron instantaneously equal to twice the initial value?

im having a lot of trouble with this problem i don't even know how to approach it can anyone pls help me to get started u..u

The sum of the kinetic energy (1/2)mv^2 of the electron plus it's potential energy in the field of the proton k*(-e)*(e)/r is a constant (note potential energy is negative!). At large r essentially all of the energy is kinetic. Find that. Now find the energy when v is doubled. At what value of r does the total energy balance?

I can provide some guidance on how to approach this problem. The first step is to understand the concepts of conservation of energy and electric potential in relation to the movement of electrons and protons.

Conservation of energy states that energy cannot be created or destroyed, it can only be transferred or converted from one form to another. In this case, the initial kinetic energy of the electron (due to its speed) will be converted into electric potential energy as it approaches the fixed proton.

Electric potential is the amount of energy required to move a unit charge from one point to another in an electric field. In this case, the electric potential is due to the attraction between the positively charged proton and negatively charged electron.

To solve this problem, we can use the conservation of energy equation:

Initial kinetic energy = final electric potential energy

We know the initial kinetic energy of the electron (due to its initial speed) and we can calculate the final electric potential energy at any distance from the proton using the equation:

Electric potential energy = (charge of electron x charge of proton)/distance between them

Now, we need to find the distance at which the speed of the electron is twice its initial value. This can be done by setting the final kinetic energy (due to the electric potential) equal to twice the initial kinetic energy. This will give us the distance at which the speed of the electron is twice its initial value.

I hope this helps you get started on solving the problem. Remember to always use the relevant equations and concepts to guide your approach.

## 1. What is the conservation of energy?

The conservation of energy is a fundamental law of physics stating that energy cannot be created or destroyed, only transformed from one form to another.

## 2. How does the conservation of energy apply to electrons?

Electrons are subatomic particles that carry electric charge and are subject to the laws of conservation of energy. This means that in any given system, the total amount of energy carried by electrons must remain constant.

## 3. What is electric potential?

Electric potential is the amount of energy that a charged particle, such as an electron, possesses due to its position in an electric field. It is measured in volts (V) and is a representation of the potential energy per unit of charge at a specific point.

## 4. How is electric potential related to the conservation of energy?

The conservation of energy dictates that the total energy of a system, including electric potential energy, must remain constant. This means that if the electric potential at a point decreases, the kinetic energy of the electrons at that point must increase to maintain the total energy of the system.

## 5. How is the conservation of energy applied in practical applications involving electrons and electric potential?

The conservation of energy is essential in designing and understanding electronic devices, such as batteries and circuits. It ensures that the flow of electrons and the transfer of energy is efficient and consistent. It also helps in predicting and troubleshooting potential issues in these devices.

• Introductory Physics Homework Help
Replies
15
Views
455
• Introductory Physics Homework Help
Replies
3
Views
622
• Introductory Physics Homework Help
Replies
22
Views
1K
• Introductory Physics Homework Help
Replies
2
Views
2K
• Introductory Physics Homework Help
Replies
3
Views
1K
• Introductory Physics Homework Help
Replies
1
Views
829
• Introductory Physics Homework Help
Replies
4
Views
2K
• Introductory Physics Homework Help
Replies
23
Views
473
• Introductory Physics Homework Help
Replies
6
Views
3K
• Introductory Physics Homework Help
Replies
2
Views
1K