Magnetism and Electromagnetism

What determines the poles of a magnet?

• Voltage

• Electrons

• Protons

• Material

Which two of the following statements are true? MORE THAN ONE ANSWER

• Magnetic fields flow from north to south

• Magnetic fields can cross over

• Magnetic fields flow from south to north

• Magnetic field lines are called flux

What does the symbol φ represent?

• Flux

• Flux density

• Field strength

• Resistance

A free electron is:

• An electron that is close to the nucleus

• An electron that can break away from the atom

• An electron that is positively charged

• An electron that has neutral charge

Which one of the following statements is true?

• When an atom loses an electron it becomes an insulator

• When an atom loses an electron it becomes negatively charged

• When an atom loses an electron it becomes positively charged

• When an atom loses an electron it can attract other electrons

If a copper atom has 28 electrons would it be:

• Uncharged

• Negatively charged

• Positively charged

• Neutral

What is the symbol for magnetic field strength?

• B

• T

• mmf

• H

Which of the following statements are true? THREE ANSWERS

• Voltage is the pressure in an electric circuit

• Voltage can be expressed as potential difference

• Voltage is the flow of electricity in an electric circuit

• Voltage can be expressed as electromotive force

Fleming’s left-hand rule best describes a:

• Generator

• Transformer

• Motor

• Solenoid

Fleming’s right-hand rule best describes a:

• Generator

• Transformer

• Motor

• Solenoid