questionary.

Question 1

write 4 branches of physics.

Answer 1

optics.
thermodynamics.
aerodynamics.
electrodynamics.

Question 2

formula for velocity,

Answer 2

v = d/t

Question 3

formula for time.

Answer 3

t = d/v

Question 4

difference between vector and scalar.

Answer 4

vector — direction and magnitud.

Question 5

what does ∆ means?

Answer 5

delta — difference.

Question 6

formula for acceleration.

Answer 6

a = ∆v / t | ∆v = vf - vi.

Question 7

what does gravity makes you do if you jump of a plane?

Answer 7

fall.

Question 8

what are the three laws of motion?

Answer 8

one ; inertia — tendency of an object to keep moving.
equilibrium — net force = 0.

two ; a = fnet / m | fg = ma

three ; for every action there’s a reaction.

Question 9

write the eight forces.

Answer 9

— weight / gravitational force.
— drag force.
— static force.
— quinetic force.
— normal force.
— tention force.
— net force.

Question 10

what is equilibrium?

Answer 10

fn = 0.

Question 11

what is a force and what units do we use?

Answer 11

when an object has acceleration ; newtons.

Question 12

how do we calculate the weight of an object?

Answer 12

w = mg | m — mass ; g — gravity.

Question 13

what is the value of gravity?

Answer 13

—9.8

Question 14

units for weight.

Answer 14

newtons.

Question 15

formula for weight.

Answer 15

w = mg.

Question 16

write the simple machines.

Answer 16

— wheel n axel.
— lever.
— pulley.
— wedge.
— screw.
— inclined plain.

Question 17

difference between ‘ima’ and ‘ma’.

Answer 17

ima — ideal work.

ma — actual work.

Question 18

what is kinetic friction?

Answer 18

a force that stops something from moving.

Question 19

what is kinetic energy?

Answer 19

the energy of an object moving.

Question 20

what is potential energy?

Answer 20

the energy when an object is on its highest.

pe = mgh.

Question 21

what is static friction?

Answer 21

a force that opposes the initial movement of an object.

Question 22

what is specific heat and what is water specific heat?

Answer 22

amount of energy neede to raise one degree of heat. ; 4180 j/kg.k

Question 23

what are the laws of thermodynamics?

Answer 23

one ; energy can’t be created or destroyed.

two ; everything in nature tens to chaos.

three ; would not be.

Question 24

formula for kinetic energy.

Answer 24

ke = 1/2 mr².

Question 25

formula for potential energy.

Answer 25

ep = mgh.

Question 26

what is boiling point and freezing point of an object?

Answer 26

boiling — temperature which liquid starts transforming in gas. freezing — temperature which water turns to solid.

Question 27

what is electricity?

Answer 27

the flow of energy trough matter.

Question 28

what is heat of evaporation?

Answer 28

the energy needed to transform liquid into gas.

Question 29

what is heat of fision?

Answer 29

energy needed to melt something.

Question 30

what is a heat engine?

Answer 30

a device that turns thermal energy into kinetic energy.

Question 31

the energy tranfered between two objects is called:

Answer 31

heat.

Question 32

in which ways can heat be transfered?

Answer 32

conduction — contact. convection — fluid between them. radiation — waves.

Question 33

what is entropy?

Answer 33

the measurement of chaos.

Question 34

what are three basic particles and what are their charges?

Answer 34

proton — (+). electron — (-). neutron — (normal).

Question 35

what is static electricity?

Answer 35

forces that interact with charges that are not moving.

Question 36

formula for force.

Answer 36

f = kq1q2 / r² | q — charges.

Question 37

which are different types of magnets?

Answer 37

— permanent ; always create magnetic forcefield. — electricaly-induced ; only creates magnetic forcefield when electricity is applied. — ferromagnetic ; a metal which when you aline the particles work as a magnet.

Question 38

how can you produce electromagnetism?

Answer 38

introducing electricity in a conductor.

Question 39

what are the parts of a transverse wave?

Answer 39

— crest ; highest point. — trough ; lowest point. — rest ; equilibrium point 0. — wavelength ; distance from crest to crest. — amplitude ; distance from crest to rest.

Question 40

define each part of a longitudinal wave.

Answer 40

— compression ; when it is more compressed. — rarefaction ; when it spreads. — wavelength ; distance between compression to comoression.

Question 41

how does a surface wave moves?

Answer 41

circular.

Question 42

which waves deforms matter in order to exist?

Answer 42

mechanical wave.

Question 43

explain electromagnetic waves.

Answer 43

travels through forcefield.

Question 44

formula for speed.

Answer 44

s = d/t.

Question 45

formula for period.

Answer 45

t = 1/f | t — period. ; units — seconds.

Question 46

how can you find ⋌?

Answer 46

⋌ = v/f | units ; meters.

Question 47

speed of sound at room temperature through the air.

Answer 47

343 m/s.

Question 48

what wavelengths can we see?

Answer 48

400 — 700 nm.

Question 49

whag frequencies can we hear?

Answer 49

20 — 2000 hz.

Question 50

what type of wave is light?

Answer 50

electromagnetic.

Question 51

maxwell.

Answer 51

proved light was an electromagnetic wave.

Question 52

einstein.

Answer 52

proposed light photons.

Question 53

planck.

Answer 53

proved wave was particle and wave.

Question 54

what happens to light when it hits another object?

Answer 54

— transmitted. — reflected. — absorbed.

Question 55

define opaque, translucent, transparent.

Answer 55

— opaque ; absorve light. — translucent ; relfect and transmit light. — transparent ; transmit almost al the light.

Question 56

relation between luminous flux, illuminance and luminous source

Answer 56

all parts of light system.