Equations

Question 1

Equation for current

Answer 1

I=Q/t

Question 2

Equations for voltage?

Answer 2

V=w/Q

V=IR

Question 3

Resistance of a parallel circuit?

Answer 3

1/resistancet =1/R1 +1/R2….

Question 4

Equation for energy transferred?

Answer 4

E=QV

P=IV

Question 5

Equation for power and then power loss?

Answer 5

P=IV

P=I^2R

Question 6

Transformer equation for 100% efficient

Answer 6

VpIp=VsIs

Question 7

Transformer equation

Answer 7

Vs/Vp=Ns/Np

Question 8

Equation for annihilation reaction?

Answer 8

E=mc^2

Question 9

Equation for heart rate?

Answer 9

1/time period (for one beat) x 60

Question 10

What is peak frequency?

Answer 10

Hot objects always emit more of onevfrequency than any other this wavelength is called the peak frequency

The higher the temperature the more radiation it emits so higher peak frequency

Question 11

What does a hot star look like?

Answer 11

Blue due to high frequency

Question 12

How do you work out what stars are made of?

Answer 12

Use spectra as each element has its own line spectrum, compare it to stars spectra and compare positions

Question 13

Evidence for red shift?

Answer 13

Spectra of distant galaxy is shifted to left compared to earths so shows moving away

Question 14

Distance time graphs

Gradient
Negative gradient
Curves

Answer 14

Velocity
Going back
Acceleration/deceleration

Question 15

What is acceleration?

Answer 15

Change in velocity -speed or direction

Question 16

Equation for Acceleration

Answer 16

Change in velocity / change in time

Question 17

Velocity time graph

Gradient
Area
Curve

Answer 17

Acceleration
Distance travelled
Changing acceleration

Question 18

Equation for weight

Answer 18

W=mg

Question 19

What does a resultant force mean

Answer 19

Object will change urs state of rest or motion

Change in velocity - object will accelerate in its direction

Question 20

Force equation

Answer 20

F=ma

Question 21

Equation for momentum

Answer 21

Momentum=mv

Question 22

Momentum before=

Answer 22

Momentum after collision

Question 23

Equation for force

Answer 23

F=change in momentum/ time

Question 24

Work done equation

Answer 24

E=Fd

Question 25

What is power and it’s equation?

Answer 25

Rate of doing work Power=w/t=energy transferred/ time

Question 26

What is power measured in?

Answer 26

J/s

Question 27

Equation for kinetic energy?

Answer 27

Kinetic energy=0.5x mass x velocity^2

Question 28

Kinetic energy liked to work done by brakes?

Answer 28

0.5mv^2=Fd

Question 29

Equation for gravitonal potential energy

Answer 29

Gravpot=mgh

Question 30

What do falling objects do?

Answer 30

Concert GPE to KE

Question 31

4 car adaptations

Answer 31

Crumple zones Air bags Seat belts Side impact bar

Question 32

2 examples of transverse waves?

Answer 32

Light/ EM waves S- waves seismic

Question 33

Examples of longitudinal waves?

Answer 33

Sound waves | P-waves (seismic)

Question 34

Equation for speed of a wave?

Answer 34

S=f x wavelength

Question 35

What feature of a wave doesn’t change once it’s left the source?

Answer 35

Frequency

Question 36

What is the law of reflection

Answer 36

Angle of incidence=angle of reflection

Question 37

What is the range of human hearing?

Answer 37

20kHz

Question 38

Speed of em wave in a vacuum?

Answer 38

3x10^8

Question 39

Order of Em from largest wave length

Answer 39

``` Radio Micro Infrared Visible Ultra violet X-ray Gamma ```

Question 40

Radio waves

Answer 40

Communication Long wave=diffract around earths surface Diffract around hills etc Short wave- radio and tv Travel long as reflected off ionosphere

Question 41

Microwaves

Answer 41

Satellites and mobile phones -pass through atmosphere Microwave ovens

Question 42

Infrared

Answer 42

Monitoring temperatures Cooking Wireless controls Optical fibres

Question 43

Visible light

Answer 43

Photography | Optical fibres

Question 44

Ultra violet

Answer 44

Detect forged bank notes Skin cancer , cataracts, pre skin aging

Question 45

Which waves can cause ionisation?

Answer 45

Ultra violet, X-ray, gamma ray

Question 46

X-rays

Answer 46

Radiography imaging

Question 47

Gamma rays

Answer 47

Cancer treatment

Question 48

Which way does energy flow?

Answer 48

From hot to cold

Question 49

What is temperature?

Answer 49

Measure of the average kinetic energy of particles

Question 50

Why doesn’t temp go down until all liquid/solid?

Answer 50

When condensing or freezing bonds are formed between particles which releases energy

Question 51

What is conduction Of heat?

Answer 51

Where vibrating particles pass on extra kinetic energy to neighbouring particles

Question 52

Equation for density?

Answer 52

D=m/v

Question 53

What is the third gas law?

Answer 53

Pressure is directly proportional to temperature when the volume is constant