Batteries and Current

Question 1

What is potential difference, and how can you measure it?

Answer 1

This difference in charge can be measured, and given a number. This difference in charge is measured in Volts (V), so potential difference is also called voltage.

Question 2

Electrical conductors- visual model

Answer 2

When there is a potential difference (voltage) between the two ends of a conductor, electrons will move towards the positive end. They move easily through good conductors, so a much smaller potential difference can induce a current flow.

Question 3

What is current?

Answer 3

Current (I) is the movement of electrons through a conductor.

Question 4

What does current measure?

Answer 4

Current measures how many electrons are moving past a point in a certain time.

Question 5

What does a small current mean?

Answer 5

A small current means not many electrons are moving past (0.5A).

Question 6

What does a large current mean?

Answer 6

A large current means lots of electrons are moving past (500A)

Question 7

What’s one Amp (A) equal to?

Answer 7

it’s equal to 6.242 times 10 times 18 (trillions of) electrons per second moving through a point

Question 8

What are amps?

Answer 8

The unit of a current (what it is measured in) is amperes, or A.

Question 9

What is potential difference?

Answer 9

Potential difference (voltage) measures the combination of the push from the negative (like charges repel) and the pull of the positive charge (opposites attract).

Question 10

What’s a visual for potential difference? + explain it

Answer 10

Potential difference is like an electrical hill, and the voltage is a measure of how steep it is. The potential difference (steepness of the hill) determines how fast each electron will move (how steep a hill is will tell you how fast they’ll run down it).

Question 11

Tell me about big vs small potential difference

Answer 11

The bigger the potential difference (the slope), the faster electrons will move, and the smaller the potential difference the slower they’ll move

Question 12

The electrical roadway analogy- current and voltage

Answer 12

If you were standing by a motorway; CURRENT is the number of cars past you in a set time (like minutes) and voltage would be the average speed of each car

Question 13

What’d new york traffic be?

Answer 13

High current, low voltage because there are lots of cars but they’re hardly moving

Question 14

What’d a race competition be?

Answer 14

High current, high voltage because there are lots of cars going very fast

Question 15

What’d a single old car be?

Answer 15

Low current, low voltage because there’s just one car and it’s hardly moving

Question 16

What’s a voltmeter measure, and how does it function?

Answer 16

Voltmeters measure voltage. The switch has to be set on = sign (this is direct current), the different numbers measure different voltages, and the black wire goes in ‘0’.

Question 17

How do batteries work?

Answer 17

When the metals are connected a series of Electromagnetic reactions between the anode (metal), cathode (metal), and electrolyte (acid). The anode experiences an oxidation reaction in which two or more ions (electrically charged atoms or molecules) from the electrolyte combine with the anode, producing a compound and releasing one or more electrons.

At the same time, the cathode goes through a reduction reaction in which the cathode substance, ions and free electrons also combine to form compounds.

The reaction in the anode creates electrons, and the reaction in the cathode absorbs them. The net product is electrons moving… electricity. The battery will continue to produce electricity until one or both of the electrodes run out of the substance necessary for the reactions to occur.