Form 5

Question 1

Resolution of forces

Answer 1

The process of resolving a force into two compounds

Question 2

Forces in equillibrium

Answer 2

An object is said to be in equilibrium of forces when the forces acting on is produces 0 resultant force

Question 3

Hooke’s Law

Answer 3

f=kx
States that the extension of a spring is directly proportional to the force applied on the string provided the elastic limit of the spring is not exceedes

Question 4

Atmospheric Pressure

Answer 4

The pressure due to the weight of the layer of air acting on the surface of earth

Question 5

Pascal’s Principle

Answer 5

States that in a fluid, an externally applied pressure is transmitted uniformly in all direction

Question 6

Archimedes Principle

Answer 6

F=pvg
States that an object which is partially/fully immersed in a fluid will experience a buoyant force which is equal to the weight of fluid displaced

Question 7

Bernoulli’s Principle

Answer 7

States that when the velocity of the fluid increases, the pressure of the fluid decreases, and vice versa

Question 8

Electromagnet

Answer 8

Is a temporary magnet, that is, acts as a magnet when the current is switched on and ceased to be a magneg when the current is switched off

Question 9

Catapult field

Answer 9

Is the resultant magnetic field produced by the interaction between the magnetic field of current-carrying conductor and the magnetic field of permanent magneg

Question 10

Electromagnetic induction

Answer 10

Is the production of induced emf in a conductor when there is a relative motion between the conductor and the magnetic field or when the conductor is in a changing magnetic field

Question 11

Faraday’s Law

Answer 11

States that the magnitude of induced emf is directly proportional to the rate of cutting of magnetic flux

Question 12

Len’z Law

Answer 12

States that the induced current always flow in a direction that opposes the change of magnetic flux that cause it

Question 13

Ideal transformer

Answer 13

Is a transformer that does not experience any loss of energy

Question 14

Step up transformer

Answer 14

Supplies output voltage that is higher than the input vtage

Question 15

Step down transformer

Answer 15

Supplies output voltage that is lower than the input voltage

Question 16

National grid

Answer 16

A network of electrical cables connecting electrical power stations to consumers of electricity

Question 17

Half life

Answer 17

Time taken for a sample of radioactive nuclei to decay to half of it’s initial number

Question 18

Radioactive decay

Answer 18

Is a process in which an unstable nucleus become more stable by emitting radioactive radiation

Question 19

Alpha decay

Answer 19

During Alpha decay, an unstable nucleus releases an Alpha particle to become a more stable nucleus of a new element

Question 20

Beta decay

Answer 20

During beta decay, a neutron of am unstable nucleus decomposes into one proton and one electron

Question 21

Gamma decay

Answer 21

During gamma decay, an unstable nucleus releases it’s excess energy to become more stable

Question 22

Nuclear energy

Answer 22

Aka atomic energy

- is released during nuclear reaction such as radioactive decay, nuclear fission and nuclear fussion

Question 23

Nuclear fission

Answer 23

Is a nuclear reaction in which a heavy nucleus splits into two or more lighter and smaller nuclei while releasing a large amount of energy

Question 24

Nuclear fussion

Answer 24

Is a nuclear reaction in which small and light nuclei fuses to form a heavy nucleus while releasing a large amount of energy

Question 25

Black body

Answer 25

Is an idealised body that is able to absorb all electromagnetic radiation that falls into it - emits thermal radiation depending on it's temperature

Question 26

Threshold frequency

Answer 26

Is the minimum frequency required to produce photoelectric effecf on a metal.

Question 27

Work function

Answer 27

Is the minimum frequency needed for a photoelectron to be emitted from a metal surface

Question 28

Quantum of energy

Answer 28

Is a discrete packet energy not a continuous energy

Question 29

Electric current

Answer 29

The rate of flow of charge in a conductor

Question 30

Potential difference

Answer 30

Is the work done to move one coulomb of charge from one point to the other

Question 31

Resistance

Answer 31

The ratio of potential difference across the conductor to the current flowing throught the conductor

Question 32

Resistivity

Answer 32

A measure of conductor's ability to oppose the flow of electric charge

Question 33

Superconductor

Answer 33

Material that conduct electricity without any resistance

Question 34

Critical temperature

Answer 34

Is the temperature when the resisitivity of a superconductor becomes zero

Question 35

Emf

Answer 35

Is the work done by an electrical source to kove one coulomb of charge in a complete circuit

Question 36

Internal resistance

Answer 36

The resistance caused by the electrolyte in the dry cell

Question 37

Power

Answer 37

Rate of transfer electrical energy