Electricty

Question 1

A.C.

Answer 1

Alternating current

Question 2

D.C.

Answer 2

Direct current

Question 3

Rms means

Answer 3

Root mean square

Question 4

Ipk

Answer 4

Peak current

Question 5

When in series, current is

Answer 5

The same everywhere

Question 6

( Series)The total resistance is the

Answer 6

Sum of all the resistors

Question 7

(Series) The sum of the voltages across the resitistirs is

Answer 7

Equal to the supply voltage

Question 8

(Parallel) the voltage across each component is

Answer 8

The same

Question 9

(Parallel) the supply current is equal to

Answer 9

The current in all branches

Question 10

I

Answer 10

Current

Question 11

r

Answer 11

Internal resistance

Question 12

What do capacitors do?

Answer 12

Store charge

Question 13

Unit of capacitance

Answer 13

Farads (F)

Question 14

Increasing the resistance in a capacitor circuit

Answer 14

Increases the amount of time for it to charge

Question 15

Conductor

Answer 15

Lets electricity flow

Question 16

Insulator

Answer 16

Does not conduct electricity

Question 17

Semiconductor

Answer 17

Conducts electricity but not very well

Question 18

Conduction requires electrons that are

Answer 18

Free to move

Question 19

In single atoms, electrons can only occupy

Answer 19

Specific energy levels with gaps in between

Question 20

When atoms combine to form solids,

Answer 20

Energy levels become wider but still with gaps in between

Question 21

Outer electrons are found in the

Answer 21

Valence band

Question 22

In an insulater, the valence bands are

Answer 22

Full

Question 23

In an insulater the next band above the valence band is the

Answer 23

Conduction band

Question 24

(Insulator) If a lot of energy is given to electrons (extreeme conditions) they can

Answer 24

Move to the conduction band and electrified conduction can now take place

Question 25

The gap between the valence and conductor bands in a semiconductor is

Answer 25

Small/narrow

Question 26

Electrons in conductors are

Answer 26

Partially free to move

Question 27

In a conductor, the valence band will

Answer 27

Be partially full or the conductor and valence band will overlap

Question 28

Doping

Answer 28

The adding of impurities to semiconductors to improve conductivity

Question 29

N-type

Answer 29

Negative charge carriers

Question 30

P-type

Answer 30

Positive charge carriers

Question 31

P-n junction

Answer 31

Electrons in n-type fill holes in the p-type so an electric field exits across the junction in the depletion layer

Question 32

Reverse bias

Answer 32

The p-n junction is connected and the cell strengthens the electric field and charges move further apart increasing the depletion layer

Question 33

What conduction takes place in reverse bias

Answer 33

No conduction

Question 34

Does conduction takes place in forward bias

Answer 34

Yes

Question 35

Forward bias

Answer 35

The cell overcomes the electrons the exist across the junction.

Question 36

Light emitting diode

Answer 36

An electron falls into the whole and a photon of light is released

Question 37

Solar cell

Answer 37

Energy of a photon lifts an electron from the valence band to the conduction band, electric field moves then causes potential difference