exam time baby

Question 1

high 2 low frequency

Answer 1

gamma (16-12), x ray(10), UV(8) ,light, infared(6-4), microwave 2), radiowaves tv longwave etc (1-8) all number to the power of 10

Question 2

properties of electromagnetic waves

Answer 2

1. waves originate from accelrating charges
2. they transfer energy from one point to another
   3.does no oscillate crets and troughs where field strongest
   4.waves can travel through vaccum (3x10^8)

Question 3

radio waves used for

Answer 3

fm radio or tv

Question 4

microwaves used for

Answer 4

heating food and satellite comms

Question 5

infared (below red) used for

Answer 5

nigth vision equipment

Question 6

visible light

Answer 6

can detect with eyes made up of rainbow

Question 7

ultraviolet

Answer 7

comes from sun

Question 8

x rays used for

Answer 8

casting shadows on x ray film and scanning bags security

Question 9

gamma rays

Answer 9

emitted during nuculear reactions can penetrate tissue

Question 10

two types of waves

Answer 10

mech and electromagnetic

Question 11

pulse

Answer 11

single disturbance in a medium.

Question 12

1khz

Answer 12

1000 hz

Question 13

1mhz

Answer 13

1,000,000 hz

Question 14

v=fh and other nb is?

Answer 14

v= h divided by 1 divided by period

Question 15

longitudal wave

Answer 15

a series of consecutive compressions and rarefractions move parallel to direction of propogation

Question 16

particle movment of longitudal wave

Answer 16

vibrate backwards and forwards parral to prop

Question 17

wave speed

Answer 17

speed at which compressions and rarefracrions move

Question 18

speed of sound waves depends on

Answer 18

how closely packed togeter particles in the medium are (energy can transfer from one particle to the next)

Question 19

how do we hear?

Answer 19

Sound Wave Reception: Sound waves travel through the air and reach the outer ear. These waves are essentially vibrations that carry energy.

Transmission in the Ear: The outer ear channels these vibrations into the ear canal, directing them toward the eardrum (a thin membrane). When the sound waves hit the eardrum, it vibrates.

Middle Ear Mechanics: The vibrations from the eardrum move a series of tiny bones in the middle ear called the ossicles (the malleus, incus, and stapes). These bones amplify and pass the vibrations to the inner ear.

Inner Ear Processing: The vibrations reach the cochlea, a spiral-shaped, fluid-filled structure. Inside the cochlea are thousands of tiny hair cells that move in response to the vibrations. This movement generates electrical signals.

Signal Transmission to the Brain: The auditory nerve picks up these signals and sends them to the brain.

Brain Interpretation: The brain processes and interprets these signals, allowing us to recognize sounds, such as speech, music, or environmental noise.

Question 20

oscilloscope does

Answer 20

converts waves into trasverse wave patterns

Question 21

higher frequency

Answer 21

higher pitch

Question 22

high loud

Answer 22

high amplitude

Question 23

at what frequencies can we not hear

Answer 23

20khz plus

Question 24

ultrasound imaging

Answer 24

Sound Waves Sent: A small device called a transducer is placed on the skin. It sends sound waves at a frequency that’s too high for humans to hear.

Waves Echo Back: These sound waves travel into the body and bounce back when they hit something solid, like an organ or tissue.

Computer Processing: The returning echoes are picked up by the transducer, and a computer converts them into images on a screen. The speed and strength of the echoes help determine the shapes, sizes, and types of structures inside.

Image Display: The result is a live, moving image that shows what’s happening inside, making it helpful for observing things like blood flow or fetal development.

Question 25

james maxwell

Answer 25

proposed that when charges accelerate there is a changing magnetic field surroundig them.

Question 26

plancks constant (max planck)

Answer 26

6,63x10^-34 j.s

Question 27

what did max planck propse

Answer 27

energy not emitted in continous manner but emitted in small energy parcels called quanta

Question 28

wave particle duality

Answer 28

some aspects of emradiation can be explained better using a wave model while some a particle model

Question 29

conversion for electromagentic radiation

Answer 29

1 micro meter times 10^-6
1 nano meter times 10^-9

Question 30

a magnet is

Answer 30

an object which has opposite magnetic poles at each end

Question 31

what type of magnet is an electromagnet

Answer 31

temporary magnet

Question 32

draw magnetic field, and replusing an attracitng

Answer 32

did u do it

Question 33

magnetic declination

Answer 33

earths magetic poles are not same as geographic poles, angle between magnetic north and geograohic true north is called magnetic declination

Question 34

electrostatics

Answer 34

study of elec at rest

Question 35

how are electrons added or removed

Answer 35

friction

Question 36

in the triboelectric series

Answer 36

further two substaces apart the greater chargine effect will be

Question 36

size of force with which charged objects attract or repel depends on

Answer 36

size of charge on object bigger=more
distance between charged objects smaller=more

Question 37

Qe is

Answer 37

1.6 x 10 ^-19

Question 38

two requirments befor chagre can flow

Answer 38

1. circuit must be closed no breaks
   2.charges mus have energy able to move

Question 39

qe

Answer 39

q,6 times 10 to the negatuve 19

Question 40

1nc is

Answer 40

1 times 10 to the negatuve 9

Question 41

resistor factors

Answer 41

1. the longer the conductor the greater its resistance
2. greater the cross sectional area the smaller its its resistance
3. the hotter the resistor the greater the resistance
4. the type of material resistance is made form

Question 42

what is a rheostat

Answer 42

an electral instrument used to control current by varying resitance

Question 43

two househild items that use a rheostat

Answer 43

ovens and light dimmers

Question 44

vi must always be given

Answer 44

yes