Question

1. Can one use energy conservation with electricity concepts?

2. What is the difference between potential and potential difference?

3. What is the relationship between electric field and potential?

4. Write down a phenomenon that involves potential or potential difference?

5. How is potential in static electricity related to potential in current-carrying circuits?

Answer 1

1- In the future, civilization will be forced to research and develop alternative energy sources. Our current rate of fossil fuel usage will lead to an energy crisis this century. In order to survive the energy crisis many companies in the energy industry are inventing new ways to extract energy from renewable sources. While the rate of development is slow, mainstream awareness and government pressures are growing. This page contains articles about the future of energy technologies.

While solar-power electric hybrid vehicles are a proven success story on the roads, the time is ripe for the appearance of solar-electric watercraft. Already a pontoon boat - Loon - is available in the market. It is solar-electric powered and can seat eight passengers. Now a smaller one - the purely electric run, Infinyte I4 - is the new kid in the block.

2- Difference between potential and potential difference

• Electric potential energy is a type of potential energy that results from Coulomb forces. The potential energy (UE) between charges q and Q can be calculated as a function of distance between the charges (r): UE(r)=qQ4??0r.

• The formula for potential energy can be modified for potential between many charges, so long as the interactions of each charge with every other charge in the system are considered. For example, potential between three charges can be solved using the following formula: UE=14??0r(Q1Q2r12+Q2Q3r23+Q1Q3r13)

• 3 - relationship between electric field and potential

• The electric field is a measure of force per unit charge; the electric potential is a measure of energy per unit charge.

  For a uniform field, the relationship between electric field (E), potential difference between points A and B (?), and distance between points A and B (d) is: E=???dIf the field is not uniform, calculus is required to solve.

  4-

  • Potential is a property of the field that describes the action of the field upon an object.

Potential at a point is the potential energy possessed by a unit charge placed at the point.
Potrential is different from potential energy. Potential energy per unit charge alone is potential. The unit charge is to be noted.

Potentials are measured in volts.

The potential difference is the difference in potentials between two points Aand B.

The difference in potentials measured between A and B is also equal to the work to be done on a unit charge to move it from B to A.In electricity, most of the time we happen to know only the potential difference rather than the actual potentials at the point.

Given two points in the space, called A and B, voltage is the difference of electric potentials between those two points. From the definition of electric potential it follows that: Voltage is electric potential energy per unit charge, measured in joules per coulomb ( = volts).

5-

Electrical circuits may be connected to ground (earth) for several reasons. In mains powered equipment, exposed metal parts are connected to ground to prevent user contact with dangerous voltage if electrical insulation fails. Connections to ground limit the build-up of static electricity when handling flammable products or electrostatic-sensitive devices. In some telegraph and power transmission circuits, the earth itself can be used as one conductor of the circuit, saving the cost of installing a separate return conductor (see single-wire earth return).

For measurement purposes, the Earth serves as a (reasonably) constant potential reference against which other potentials can be measured. An electrical ground system should have an appropriate current-carrying capability to serve as an adequate zero-voltage reference level. In electronic circuit theory, a "ground" is usually idealized as an infinite source or sink for charge, which can absorb an unlimited amount of current without changing its potential. Where a real ground connection has a significant resistance, the approximation of zero potential is no longer valid. Stray voltages or earth potential rise effects will occur, which may create noise in signals or if large enough will produce an electric shock hazard.