Name two types of media that sound can travel through and one type of media that sound can NOT travel through.
Air, metal, water .. anything that allows sound to travel through!
Can't travel through space.
100
'White' visible light is a mixture of which colors?
Red, Orange, Yellow, Green, Blue, Indigo and Violet.
100
List 4 forms of energy
Potential energy (gravitational potential, chemical potential, elastic potential)
Kinetic energy (kinetic, light, sound, heat, electrical, magnetic)
100
What is a medium?
The material through which a wave travels.
100
Draw a Sankey diagram of a light bulb with initially 100 J of energy where 20 Joules of energy goes to light
---------------------> -------------> 20 J light
100 J ------> 80 J Heat
80 J arrow should be curved and 4 times thicker than the 20 J arrow.
total thickness of 80 J arrow and 20 J arrow should equal thickness of 100 J initial arrow
200
Name the following parts of the ear:
a) Is on the outside of our head and catches the sound waves from the environment?
b) receives vibrations FROM the ear drum and passes them TO the anvil?
c) sends the electrical signals to the brain?
a) The pinna
b) the hammer
c) the auditory or cochlea nerve
200
Name the parts responsible for the following functions:
1) Contains rods and cones that transform the light energy into electrical messages
2) Bends the light rays and focuses them onto the back of the eye ball.
3) Controls the size of the pupil
a) Retina
b) Lens
c) Iris
200
Describe the law of conservation of energy and what it means.
Energy can not be created or destroyed, it simply changes from one form to another.
This means that energy never 'disappears' or gets made, it is always just changing the form it is in.
200
Which part of a wave does AMPLITUDE refer to?
The height of the wave. The distance from the resting position to the crest or to the trough.
200
What is the name of the jelly like substance that takes up most of the space of the eye ball?
Vitreous humor
300
Mrs Ferris asks her class to reduce the amplitude of their sound waves - what is she asking them to do?
To be quiet!
300
If I change the wavelength of visible light, what would I SEE?
A change in color of the light
300
What type of energy does an apple have?
Chemical potential energy
300
What does the anvil do?
Takes vibrations from the hammer (the kinetic energy from the hammer) and transfers the vibrations to the stirrup (as kinetic energy)
300
Draw a displacement-distance graph for a wave with an amplitude of 3 cm and a wavelength of 4 cm with two crests and two troughs.
ask your teacher to check your answer.
400
Mr O'Brien hums a very low frequency note for 5 seconds, he then triples his frequency of note (keeping the amplitude the same) for the next 5 seconds.
Draw a diagram of two waves.
Your two waves should both have the approximate same height.
The waves should take up the same distance (to represent 5 seconds) yet the second wave should 3x the number of complete waves than the first wave.
400
If I decreased the AMPLITUDE of a visible light wave, what would I see?
The light would get dimmer (less bright)
400
Name three energy transformations that a electric oven makes.
Electric to heat
Electric to light
Heat to kinetic (warm air particles move and circulate in the oven)
Electric to chemical potential (if you are cooking food, the food is the chemical potential bwa ha ha ha haaaa)
400
What is the frequency of a wave?
The number of complete waves that pass a fixed point in an amount of time (for example in a second).
400
Draw a displacement-time graph with an amplitude of 3 cm and a frequency of 2 Hz with 2 crests and 1 trough.
check with your teacher
500
Draw a sound wave (what it ACTUALLY should be drawn as) and label the rarefactions and compressions.
How would you determine or judge amplitude of this wave?
Label your diagram to show one wavelength.
Your wave must show particles that are clumped together (compression) and then space between them (rarefaction).
To judge amplitude you have to look at how tightly packed together the particles are in the compression area.
Wavelength should be labelled from one compression to the next.
500
Explain why you have a 'blind spot' .
On the back of retina are rods and cones that change the light energy into electromagnetic energy so that your brain can understand what you are seeing. This electromagnetic energy is transferred along a nerve (the optic nerve) which goes to your brain. At the point where the optic nerve goes from the back of your eye to your brain, there are no rods or cones so any light hitting that spot is not interpreted.
500
A person sky dives (jumps out of a plane with a parachute on), describe the major energy transformations that take place during the following parts of the experience:
- sitting at the edge of the plane door (about to jump)
- free falling after they jump from the plane
- opening of the parachute and slowing down
Sitting at the plane door = gravitational potential energy
turns into kinetic energy as they fall
turns into heat (air resistance/friction) as they slow down due to the parachute
500
What type of wave is visible light?
Electromagnetic.
500
Draw two displacement time graphs where the second graph has twice the amplitude and twice the frequency of the first one.