What are the advantages of photocells?
Robust
do not need maintenance
no fuel needed
no long power cables needed
no pollution
do not contribute to global warming
use a renewable energy resource
They do not work when dark or cloudy
They produce no CO2 emissions in their total product lifetime
Photocells are made of a conductive material - silicon
Glass is transparent to...
Short wavelength radiation
Long wavelength radiation
Solar reflectors are moved by the computer to ensure that they are always facing the sun
The energy produced by a wind farm depends upon...
the size of the wind turbine
the speed of the wind
the direction of the wind
Some people hate wind turbines because they spoil the view
The current from a dynamo can be increased by...
Using a stronger magnet
Increasing the number of turns on the coil
Rotating the magnet faster
Using thinner wire to decrease resistance
Increase the surrounding temperature
Slowing down the magnet
Moving the magnet up and down, as well as rotating it
