Charge and Current

Question 1

Define electric current

Answer 1

The movement of electrons in metals and movement of ions in electrolytes

Question 2

What is the units of current?

Answer 2

Amperes

Question 3

What is the equation for current?

Answer 3

Change in Q/Change in t

Question 4

Define 1 ampere

Answer 4

1 ampere is equal to 1 coulomb of charge passing a given point per second

Question 5

What is the unit of charge?

Answer 5

Coulomb

Question 6

What is the value of the elementary charge?

Answer 6

1.6 x 10^-19

Question 7

What direction is conventional current?

Answer 7

From the positive terminal to the negative terminal

Question 8

What direction is actual electron flow?

Answer 8

From negative terminal to the positive terminal

Question 9

What is Kirchoff’s first law?

Answer 9

For any point in an electrical circuit, the total sum of currents into that point is equal to the total sum of currents out of that point

Question 10

What is the law of conservation of charge?

Answer 10

It states that electrical charge can neither be created nor destroyed

Question 11

What is the mean drift velocity of charge carriers?

Answer 11

The average velocity of electrons as they move through a wire

Question 12

What is the equation of current with mean drift velocity?

Answer 12

I=Anev

Question 13

What is the order in terms of number density, from highest to lowest, of conductors, semiconductors, and insulators?

Answer 13

Conductors, semiconductors, insulators

Question 14

How does the mean drift velocity change with the cross sectional area?

Answer 14

If cross-sectional decreases, the mean drift velocity increases in order to keep current constant. So cross sectional area is inversely proportional to mean drift velocity