3.2 Static Electricity

Question 1

Static electricity is the result of?

Answer 1

Imbalance between negative and positive charges

Question 2

What are the causes of static electricity?

Answer 2

friction, pressure and separation, this process is called the tribo electric effect

Question 3

What effects a static charges magnitude?

Answer 3

material composition, applied forces, separation rate and relative humidity.

Question 4

Materials high on the tribo chart =? and lower =?

Answer 4

Positively charged (lose electrons), lower = negatively charged (gain electrons)

Question 5

Coulombs law states?

Answer 5

Charged bodies attract or repel each other with a force that is directly proportional to the product of their individual charges, and is inversely proportional to the square of the distance between them.

Question 6

The amount of attracting or repelling force which acts between 2 static bodies depends on 2 things?

Answer 6

Their charges and the distance between them.

Question 7

What is the symbol for Coulombs?

Answer 7

C

Question 8

What is the symbol for charge?

Answer 8

Q

Question 9

What does 1 Coulomb =

Answer 9

1C = 6.25 x 10 to the power of 18 electrons

Question 10

What does coulombs measure?

Answer 10

quantity of electric charge

Question 11

What is conduction current?

Answer 11

The movements at speed of light of the electrons jumping from one atom to the other atom to reach the end of the conductor.

Question 12

How are electrons conducted in a solid

Answer 12

Via movement of electrons.

Question 13

How are electrons conducted in a liquid.

Answer 13

It depends on the liquids ability to form ions (positive or negative charged atoms), positive and negatively formed ions will attract to the opposites of the polarity electrodes..

Question 14

Conductivity of liquids

Answer 14

Liquids which are able to conduct ionically are known as electrolytes

Question 15

Most electrolytes are?

Answer 15

Acid, Alkali or Salt solutions.

Question 16

How are electrons conducted into gas?

Answer 16

Heat or high electrical potentials can dislodge electrons or cause them to move into the atoms of a gas, ionising the gas, With the gas ionised conduction current can pass.

Question 17

Explain thermionic emission

Answer 17

When heating a conductor to a high enough temperature the free electrons will boil off the surface of the conductor. called thermionic emission.

Question 18

How is electron current created in a vacuum?

Answer 18

By heating the cathode via thermionic emission which forces the electrons off the surface which then the electrons are attracted across to the anode via electrostatic attraction.