Energy efficiency can be described as the ratio of useful energy divided by _____________ energy
Total
15
A footballer's leg kicks a stationary football. An energy transformation or ernegy transfer?
Transfer
15
What does sound energy travel through to get to your friend's ears?
air usually
15
Sound and light waves can both travel through the vaccuum of space T or F
False - only light can travel throug a vacuum/
15
You want to build a soundproof room in your basement (for music) suggest two good material to line the walls
foam, egg containers, soft blankets, padding
15
Heat energy travells from a _________ temperature object to a _________ temperature object
high to low
15
What are the three forms of heat thransfer?
radiation, convesction & conduction
15
light waves, radio waves, wifi are all forms of ________________ radiation
electromagnetic
15
What term is used to describe how often a wave repeats in a given time?
frequency
15
standing 10 meters from a bonfire you feel the heat. has the heat travelled to you by radiation in a straight line or by blowing convection air currents?
radiation in a straight line
15
cool water in a pot on the stove rises up as it is heated and starts to form _____________ currents in the water
convestion
15
Sam takes handwarmers to the snow to put in his gloves. They contain metal that reacts with air when exposed. This is an energy transfer of _____ energy to _______ energy
15
200 joules of light energy are measured coming from a light globe consuming 1000 Joules of energy. How efficient is the globe?
200/1000 = 20%
15
Energy isnt created or destroyed, just changed. Explain how this works as a bungy jumper leaps off the bridge
Gravitational potential is converted to kinetic and then to elastic potential as they get to the bottom.
15
Hertz is the number of cycles per second of a wave - what is the unit used to measure amplitude or loudness?
