In effect they form a separate retinal system for operating in daylight. Rods outnumber cones by 20:1 and are 1000 times more sensitive to light. All photoreceptors do essentially the same thing, they
3. How do the three parts of a speaker--electromagnet, cone, and diaphragm--work together to make sound? The three parts come together and make sound by the audio signals being sent through a wired coil and a piece of iron called an electromagnet. The electromagnet is connected to a cone or diaphragm which when the electromagnet
Sound waves travel through the fluid of the cochlea and make the hair cells in the organ of Corti move. The hair cells are the receptors for hearing. When the hairs bend, they cause an
The outer ear consists of the pinna which collects the sound and transmits it to the ear canal, which amplifies the sound and transmits it to the tympanic membrane, the division between the outer ear and the middle ear. The middle ear consist of tympanic membrane, osiccles (three bones connected in sequence: hammer, anvil and stirrup) and oval window. When the sound vibration from the outer ear reaches the tympanic membrane it vibrates at the same rate as the vibration from the outer ear. The vibrating tympanic membrane causes ossicles to vibrate, which transmits the vibration to the oval window. The sound is amplified when transmitted as the tympanic membrane is much larger then the oval window, and the bigger force is needed to transmit the vibration from the air module to the fluid filled cochlea of the inner ear.
The speech processor is a computer that analyzes and digitizes the sound signals and sends them to a transmitter worn on the head just behind the ear. The transmitter sends the coded signals to an implanted receiver just under the skin. The internal (implanted) parts include a receiver and
We will use coloured filters (first red and then continue in rainbow order) to gain coloured light. We will use slots to get a singular ray of light that we can shine down the angle of incidence for the perspix which we will have to keep the same as a control. For example the angle of incidence could be 30° because it has to be quite low so that it doesn’t cause total internal refraction. Then we will measure the refractive index that comes out of the perspix block from the normal line using a protractor. We will record the results in a results table (in the column heading measure it in °).
What is an absolute threshold? [2 marks] - An absolute threshold is the minimum amount of energy needed for a specific sensory system to detect a stimulus in the environment at least 50% of the time. 3. Explain how light is converted into electrochemical impulses in the brain. [3 marks] - Light travels through the pupil to the retina where it contacts the photoreceptors (rods and cones) and bleaches a pigment in the photoreceptors, which creates graded receptor potentials
Continuous spectrum: a spectrum that exhibits all the wavelengths of visible light 13. Line Spectrum: a spectrum showing only certain discrete wavelengths 14. Quantum model: The quantum mechanical model is based on quantum theory, which says matter also has properties associated with waves. According to quantum theory, it’s impossible to know the exact position and momentum of an electron at the same time 15. Ground state: the lowest possible energy state of an atom of molecule 16.
Notice that the angle of incidence at the first surface is equal to the angle of refraction at the second surface. Prove algebraically (using Snell’s Law twice) why this is true. n1sin θ1=n2sin θ2 n2sin θ2=n1sin θ3 n1sin θ1=n1sin θ3 sin θ1=sin θ3 5. Do different colors refract at different angles? No, difference colors do not refract at different angles.
Measuring the Velocity of Sound by Air Column Raw Data Quantitative Data Frequency (Hz) | Height (m) ±0.005 | 256.0 | 0.320 | 288.0 | 0.290 | 320.0 | 0.250 | 341.3 | 0.240 | 426.6 | 0.190 | 512.0 | 0.155 | Qualitative Data The height of the air column would have been a slight approximation, as it was difficult to determine the exact position of the pipe which emitted the strongest sound. The ruler used to measure the height of the air column was accurate to 1mm; therefore the uncertainty for these measurements was ±0.005m. The ruler was often accidentally placed above or below the water, as it was difficult to maintain it at the surface of the water. The error of Parallax would have been present when reading the measurements of the ruler, as the student often read the ruler from above. It was not certain that the ruler was parallel to the air column, and could have skewed the measurement of the height of the air column as longer than it realistically was.