Hydroelectricity

Question 1

potential energy

Answer 1

stored energy, pe=mgh

Question 2

kinetic energy

Answer 2

energy of movement, ke=1/2xmassxvelocity(2)

Question 3

tides

Answer 3

sun/moon gravitational pull differences, sun is stronger moon is closer, 2 high and low tides a day, 12.5 hrs apart, 50 mins later each day

Question 4

force

Answer 4

mass1 - mass2 /distance

Question 5

tidal bulge

Answer 5

bigger pull on one side by moon

Question 6

inverse law

Answer 6

as distance increases force decreases, 1/d(2)

Question 7

why does moon have bigger pull than sun

Answer 7

as its closer to earth, 1/dist(2)

Question 8

high tide

Answer 8

nearest and furthest from moon

Question 9

low tide

Answer 9

moon is right angle to earth

Question 10

spring tides

Answer 10

moon and sun allign

Question 11

neap tides

Answer 11

moon and sun at 90 degrees

Question 12

hydroelectricity

Answer 12

water builds up at top as PE and is released and turned to KE and energy is extracted through turbine

Question 13

tidal power

Answer 13

uses tidal movements to extract energy, ocean not enough energy, estuaries have high amplitude

Question 14

tidal flow systems

Answer 14

propellers extract KE between 2 islands

Question 15

tidal barrage systems

Answer 15

holds high tide at barrage/dam and extracts energy as water flows out barrage

Question 16

power of tidal barrage

Answer 16

1/2 x water density x area x gravity x height (2)

Question 17

height

Answer 17

difference between height of high and low tide

Question 18

power available in barrage

Answer 18

1/2 x water density x gravity x area x height(2)/2 x T

Question 19

T

Answer 19

12.5 x 3600

Question 20

Ebb tide system

Answer 20

2 bursts a day, water fills at high tide and flows out as outside water drops and generates electricity

Question 21

efficiency of tidal turbines

Answer 21

80%

Question 22

amplitude

Answer 22

wave height

Question 23

frequency

Answer 23

number of waves per second (hertz)

Question 24

velocity

Answer 24

speed

Question 25

wavelength

Answer 25

difference in peaks

Question 26

wave equation

Answer 26

velocity = wavelength x frequency