Right hand rules

Right-hand rule #1 (RHR#1) for conventional current flow: Grasp the conductor with the thumb of the right hand pointing in the direction of conventional, or positive (+), current flow. The curved fingers point in the direction of the magnetic field around the conductor.

Right-hand rule #2 (RHR#2) for conventional current flow: Grasp the coiled conductor with the right hand such that curved fingers point in the direction of conventional, or positive (+), current flow. The thumb points in the direction of the magnetic field within the coil. Outside the coil, the thumb represents the north (N) end of the electromagnet produced by the coil.

Right-hand rule #3 (RHR#3) for conventional current flow; the motor principle: Open the right hand so that the fingers point in the direction of the magnetic field (from north to south). Rotate the hand so that the thumb points in the direction of conventional (+) current flow. The orientation of the palm indicates the direction of the force produced.

Notes from pg 582-589

1) A magnetic field is the distribution of a magnetic force in the region of a magnet.

2) Similar magnetic poles, north and north or south and south, repel one another with a force at a distance. Dissimilar poles, north and south or south and north, attract one another with a force at a distance.

3) To map a magnetic field, we use a test compass. A test compass is a compass that is used to check for the presence of a magnetic field.

4) Field lines show the direction in which the north seeking pole of this test compass would point at that point in space.

5) Earth acts like a giant permanent magnet creating its own magnetic field. It is suggested that Earth's magnetic field is produced because of the flow of hot liquid metals inside the Earth.

6) Metals such as iron, nickel, cobalt, or mixtures of these three that attract magnets are known as ferromagnetic metals. Ferromagnetic elements have an atomic structure that seems to make them strongly magnetic.
7) Domain theory of magnets: All large magnets are made up of many smaller and rotatable magnets, called dipoles, which can interact with other dipoles close by. If dipoles line up, then a small magnetic domain is produced.
8) Oersted's Principle: Charge moving through a conductor produces a circular magnetic field around the conductor.

9) Right-hand rule #1 (RHR#1) for conventional current flow: Grasp the conductor with the thumb of the right hand pointing in the direction of conventional, or positive (+), current flow. The curved fingers point in the direction of the magnetic field around the conductor. 

10) Right-hand #2 (RHR#2) for conventional current flow: Grasp the coiled conductor with the right hand such that curved fingers point in the direction of the conventional, or positive (+), current flow. The thumb points in the direction of the magnetic field within the coil. Outside the coil, the thumb represents the north (N) end of the electromagnet produced by the coil.

11) RHR#2 predicts the relationship between the direction of conventional current flow in a coil and the direction of the magnetic field at the end of the electromagnet.
12) Electromagnet is a coil of wire around a soft iron core, which uses electric current to produce a magnetic field.

Notes from pg 553-563

1)The amount of current flow in a circuit and therefore the amount of energy transferred to any useful device, depends on two things:
-the potential difference of the power supply(the amount of push) and
-the nature of the pathway through the loads that are using the electric potential energy.
2)A measure of the opposition to the current flow in a circuit is known as the resistance.
3)The current and the potential difference have a direct relation because as the current in a circuit increases the voltage tends to increase as well, as long as other variables such as temperature, are controlled. There is a resistance of 1 Ω when 1 A of current flows with a potential difference of 1 V across a resistor.
4)The Ohm's law states that the V/I ratio is constant for a particular resistor. (R=V/I)

5)Where "R" is the resistance in volts/ampere, which is given the derived unit of ohm (Ω), after Georg Simon Ohm (1787-1854), V is the potential difference in volts and I is the resulting current in amperes (A).

6)The resistance of a conductor depends on its length, cross-sectional area, the material it is made of and its temperature.

7)In a series circuit, the loads are connected one after another in a single path, whereas in a parallel circuit, they are connected side by side.

8)The Kirchhoff's current law states that the total amount of current into a junction point of a circuit equals the total current that flows out of that same junction.

9)Kirchhoff's voltage law states that the total of all electrical potential decreases in any complete circuit loop is equal to any potential increases in that circuit loop.

10)We can determine the overall resistance of series or parallel circuit elements by applying both Ohm's law for resistance and both of Kirchhoff's laws.

Prelab: Using Voltmeter and Ammeter

    Name          Symbol          Unit           Definition
1)Voltmeter          V                 V             A voltmeter is used to measure the voltage.
2)Current              I                  A             The total amount of charge moving past a point in a condutor.

3)Resistance         R                                 A measure of the opposition to current flow.
4)Power               P                 W            The rate at which work is done.    

Newspaper Structure Activity

1) Our structure was wide at the bottom but it was not strong or stable enough to hold the whole model together. The model got thinner and since we rolled the newspaper more, it got heavier and fell down at the end.
2) A wide and strong base makes a tall structure stable. Also the less the mass of the structure, the more stable it is since heavy structure lean or fall down quickly.
3) The centre of the gravity is the base of the structure which hold the model together.

Notes on current electricity

1)Electrons in a static state have energy but they are most useful when they transfer their energy.
2)In order for current to flow the electrons should have a path to follow from negative to positive side of the power supply. This path is known as the circuit.

3)In DC (Direct Current) the current flow in one direction, from the power supply ,through the conductor, than the device that needs energy and than finally back to the power supply.

4)In AC(Alternating Current) the electrons can follow the path backwards and can reverse their direction. This could be done with the help of electric and magnetic forces.

5)The model of positive charge flow is known as the conventional current.

6)The energy delivered to the load (the device that uses energy and/or converts it) depends on the potential i-e the energy per charge and the rate at which the charge is delivered (the current).

7)A voltmeter is an instrument used to measure potential difference between any two points.
8)A voltemeter must be connected in parallel with a load in the circuit so that the potential is measured and compared equally before and after the load.
9)The voltmeter must have large resistance so that even if the conductor is poor to which the load is connected, the measurement by the voltmeter could divert the minimal current from the circuit.

10)In order to understand circuits better, we use symbols so that it is easier and convenient to understand.

11)There are many various devices that convert the electrical potential energy one source to various different forms. The original form can be chemical, mechanical, thermal or light energy.

12)Important equations for this unit:

   *Current is the rate of charge flow and is given the symbol "I". Current is the total amount of charge moving past a point in a conductor divided by the time taken. The formula is I=Q/T(Where I is the current in amperes (A), Q is the charge in coulombs (C) and t is the time in seconds)
   *The electrical potential energy for each coulomb of charge in a circuit is called the electrical potential energy. The formula isV=E/Q(Where V is the voltage, E is the energy required to increase the electrical potential of a charge Q)
   *The energy transferred by the charge flow is E=VIt(Where E is the energy in joules, V is the potential difference in volts, I is the current in amperes and t is the time in seconds)