Sensing Electrically

Question 1

What is electric charge?

Answer 1

A property of certain particles that determines its electromagnetic interactions.

Question 2

What are the two types of electric charge?

Answer 2

• Positive
• Negative

Question 3

How is electric charge measured?

Answer 3

In coulombs.

Question 4

What does the conservation of charge state?

Answer 4

Electric charge can’t be destroyed nor created, it can only be transferred from one object/form to another.

Question 5

What is an electric dipole?

Answer 5

Consists of two equal but opposite charges separated by a distance.

Question 6

Give examples of electric dipoles.

Answer 6

• HCl
• H₂O
• CH₃COOH

Question 7

What are the imaginary lines of force for positive and negative charges?

Answer 7

Positive charge has lines facing outward and negative charge faces inward.

Question 8

True or False: The lines of force never intersect.

Answer 8

True.

Question 9

What happens to like and unlike charges?

Answer 9

• Like charges repel
• Unlike charges attract

Question 10

What is conduction?

Answer 10

The process where heat or electricity is directly transmitted through a material without the movement of the material.

Question 11

What are conductors?

Answer 11

Materials that allow electric current (e.g., copper, aluminum).

Question 12

What is insulation?

Answer 12

The process of preventing electricity from traveling through a material.

Question 13

What are insulators?

Answer 13

Materials that resist electric current (e.g., rubber, glass).

Question 14

Fill in the blank: Static electricity transfers charges through _______ and induction.

Answer 14

conduction

Question 15

What is electric current?

Answer 15

The flow of electric charges (electrons) through a conductor.

Question 16

What is the unit for measuring electric current?

Answer 16

Amperes (A).

Question 17

What is electromotive force?

Answer 17

The force that acts on the electrons to make them move in a certain direction.

Question 18

What is the relationship between electromotive force and voltage?

Answer 18

Electromotive force is known as voltage and is measured in volts.

Question 19

What does Faraday’s law of electromagnetic induction state?

Answer 19

A change in magnetic field around a conductor induces an electric current in the conductor.

Question 20

What is the difference between direct current (DC) and alternating current (AC)?

Answer 20

• DC flows in one direction
• AC changes direction periodically

Question 21

What is the purpose of transformers in AC transmission?

Answer 21

To allow AC to be transmitted over long distances with less power loss.

Question 22

What is potential difference?

Answer 22

The difference in the amount of energy that charge carriers have between two points in a circuit.

Question 23

What is the formula for potential difference?

Answer 23

V = I x R

Question 24

What is electrolysis?

Answer 24

The flow of electrical current in a conducting solution or a molten liquid that causes chemical changes.

Question 25

What is an electrolyte?

Answer 25

A substance that has a natural positive or negative electric charge when dissolved in water.

Question 26

What happens at the anodes and cathodes during electrolysis?

Answer 26

* Anions attach to anodes * Cations attach to cathodes

Question 27

What does the acronym OIL RIG stand for?

Answer 27

Oxidation is Loss and Reduction is Gain.

Question 28

What is the reactivity series?

Answer 28

The arrangement of metals in descending order of their reactivities.

Question 29

What are powerful reducing agents in the reactivity series?

Answer 29

Metals at the top of the reactivity series.

Question 30

What is electroplating?

Answer 30

A process by which a metal object is coated with a layer of another metal through electrolysis.

Question 31

What is bioelectrogenesis?

Answer 31

The ability of organisms like bacteria to produce electricity.

Question 32

What does resistivity quantify?

Answer 32

How strongly a material opposes the flow of electric current.

Question 33

What is Ohm's Law?

Answer 33

The strength of direct current is directly proportional to the potential difference and inversely proportional to the strength of the current.

Question 34

What does Kirchoff’s law of voltage state?

Answer 34

The sum of all the voltages around the closed loop adds up to 0.

Question 35

What is a reflex arc?

Answer 35

A neural pathway that controls a simple stimulus response.

Question 36

What is the resting potential of a neuron?

Answer 36

Around -70 mV.

Question 37

What happens during depolarization?

Answer 37

The potential difference changes to around +40 mV.

Question 38

What is hyperpolarization?

Answer 38

When the inside of the neuron becomes more negative than it should be.

Question 39

What is the function of the myelin sheath?

Answer 39

To insulate the axon and speed up the electrical impulse.

Question 40

What are neurotransmitters?

Answer 40

Chemical messages secreted into the synaptic cleft to transmit impulses between neurons.