Transcript acutus mens
ACUTUS MENS “The sharp mind” 2nd Semester 2011 AM #1 1. 2. 3. 4. Define wave. Give 3 examples of media. What 2 things can waves travel through? What does a wave carry? ANSWERS 1. Periodic disturbance in solid, liquid, or gas as energy is translated 2. Solid, liquid, gas 3. Space and matter 4. Energy AM #2 1. What kind of waves require a medium? 2. What kind of waves do NOT require a medium? 3. What do we call waves that are produced by a combination of longitudinal and transverse waves? 4. What is amplitude? 5. What is frequency? ANSWERS 1. 2. 3. 4. 5. Mechanical Electromagnetic Surface Height of a wave from the rest point How many waves pass a certain point in a specified amount of time AM #3 1. How do we calculate wave speed? 2. What is the relationship between frequency and wavelength? 3. Differentiate between reflection, refraction, and diffraction. 4. What is interference? Explain the two types of interference. 5. What is a standing wave? Give an example. 6. Explain resonance. Give an example. ANSWERS 1. Wave speed = frequency (f) X wavelength ( ); measured in hertz 2. As frequency increases; wavelength decreases and vice versa 3. Reflection – bouncing back of a wave; Refraction – bending of a wave as it changes medium; Diffraction – bending of a wave around a corner or thru a hole 4. When waves intersect; constructive – waves meet and get larger (build); destructive – waves meet and break down (noise) 5. Patterns of vibrations that stimulate a wave making it appear to stand in place (tire spinning) 6. When 2 objects vibrate naturally at the same frequency causing objects to vibrate (like base and a car mirror) AM #4 1. 2. 3. 4. What kind of wave is a sound wave? How does sound travel? In what direction do sound waves travel? Define a medium. ANSWERS 1. 2. 3. 4. Longitudinal By vibration All directions A solid, liquid, or gas AM #5 1. What are the 3 sections of the ear? 2. What are the 3 bones in the middle ear called? 3. What is responsible for transmitting sound electrically to the brain? 4. Predict what may have happened if a person has lost their hearing (answers will vary). 5. What are the 3 kinds of instruments? ANSWERS 1. 2. 3. 4. 5. Outer, middle, inner Hammer, anvil, stirrup Cochlea Answers will vary Winds, strings, percussion AM #6 1. What is pitch? How is it related to frequency? 2. What do we call sounds that have a frequency too high to hear? 3. What happens when a jet breaks the sound barrier? 4. Describe the doppler effect . 5. Define noise. ANSWERS 1. How low/high a sound appears to be; high pitch = high frequency; low pitch = low frequency 2. Ultrasonic 3. A sonic boom 4. The change in the sound based on the position of the listener or the origin of the sound. 5. A sound that consists of a random mix of frequencies. AM #7 1. Define loudness. What is the unit used to measure loudness? 2. How are amplitude and frequency related? 3. What is used to change a longitudinal sound wave into a transverse wave? 4. What is an echo? 5. What surface reflects an echo the best? ANSWERS 1. How well a sound can be heard. Measured in Decibels. 2. Increase amplitude – increase frequency (decrease wavelength) 3. Oscilloscope 4. Reflected sound wave 5. Hard, smooth AM #8 1. What is an electronic echo called? 2. What do we call the process of using sound to locate an object? 3. What medical procedure allows us to “see” inside the body without surgery? 4. Define a sonic boom. 5. What are the 2 kinds of standing waves? ANSWERS 1. 2. 3. 4. Sonar echolocation Ultrasound Constructive interference builds up and creates a sonic boom as a jet breaks the sound barrier 5. Fundamental and overtones AM #9 1. 2. 3. 4. 5. 6. Define sound quality. Define noise. What is an electromagnetic wave? Define radiation. What is the electromagnetic spectrum? List the waves of the electromagnetic spectrum in order from longest to shortest. 7. Differentiate between the 2 kinds of reflection. ANSWERS 1. 2. 3. 4. 5. 6. 7. Blending of pitches through interference. Random mix of frequencies (depends on listener). A wave that is made of electric and magnetic fields that vibrate – does not require a medium. Transfer of energy by electromagnetic waves. All the frequencies or wavelengths of electromagnetic radiation; divided based on wavelength Radio Waves – longest; used in radio signals and TV signals; Microwaves – used in microwave ovens , radar, cell phones, and satellites; Infrared – heat detection, night vision goggles; Visible Light – very narrow band (the Rainbow – ROYGBIV); Ultraviolet – produced by sun, causes sunburn, kills bacteria; X-Rays – used in detection of broken bones and security devices; Gamma Rays – used to kill bacteria on food and in treatment of specific types of cancers. Regular – reflection seen when using a flat, plane mirror; Diffuse – reflection seen when using a contoured mirror (like a fun house mirror). AM #10 1. 2. 3. 4. 5. Compare absorption to scattering. What is refraction? Give an example. Define diffraction. What are the three things light can do? What are the 3 kinds of objects and how do they relate to light? 6. When we look at an object, what color do we see? 7. What happens to the other colors? AM #10 ANSWERS 1. Absorption – light particles are absorbed by the object (very little light is reflected); Scattering – light is largely reflected (like a disco ball) 2. Bending of a wave as it changes medium; a light beam travelling through a piece of paper (gas to solid, then back to gas) 3. Bending of light around corners or through a hole (under a door, etc.) 4. Reflect, Absorb, and Transmit 5. Opaque – absorbs part of light and reflects the rest; Transparent – transmits light; Translucent – absorbs part and scatters the rest. 6. The color of light that is reflected. 7. They are absorbed. AM #11 1. What are the three primary colors of light? 2. When the 3 primary colors of light are combined in equal amounts, what do they create? 3. What is pigment? 4. What are the three primary pigment colors? 5. When the three primary pigments are added together in equal amounts, what is the result? 6. Compare the primary colors of light to the primary colors of pigments. 7. Draw a convex and concave lens/mirror. Answers 1. 2. 3. 4. 5. 6. Red, Blue, and Green White light An opaque substance that reflects and absorbs light. Cyan, Magenta, Yellow Black Light – Red, Green, and Blue – combine to make white light; Pigments – Cyan, Magenta, Yellow – combine to make black 7. Concave Convex - AM #12 1. What is a plane mirror? 2. Which type of lens magnifies? 3. Which type of lens make images appear fine and crisp? 4. What are the 2 most common vision problems? 5. What is the function of the following parts of the eye: retina, pupil, lens, optic nerve, cornea, iris? 6. Name 3 ways light affects your life (answers will vary). Answers 1. 2. 3. 4. 5. Flat mirror convex concave Nearsightedness and farsightedness Retina – back of eye, contains rods (black and white) and cones (color); Pupil – black part of eye where light passes through; Lens – convex lens that refracts light; Optic Nerve – flips image right side up and sends signals to brain; Cornea – provides shape to the eye; Iris – colored portion of the eye. 6. Cameras, Telescopes, Lasers, etc. AM #13 1. 2. 3. 4. 5. What are the properties of a magnet? What are the opposite ends of a magnet called? What is magnetic force? Explain how a magnetic field works. How can a magnet lose its’ magnetic alignment? (How can you destroy a magnetic field?) 6. How can you create a magnet? 7. How is the Earth like a magnet? 8. Explain the relationship between north and south poles on a magnet. Answers 1. 2. 3. 4. 5. 6. 7. 8. Material that attracts ferromagnetic material. poles The push or pull exerted by a magnet. The area around a magnet where t he magnetic force is effective. Striking it very hard, dropping from a very high altitude, heating it. Rub a ferromagnetic material on a strong magnet – only temporary. Has a magnetic field, made of spinning electrons Like poles repel, opposite poles attract. AM #14 1. 2. 3. 4. How does a compass work? What happens when you break a magnet? Give an example of a magnetic light show. What is generated when charges flow through a wire? 5. What is the unit used to express the amount of charge that flows through a wire? 6. What does an electric current produce? What happens if the current reverses? 7. What can electrical current flow through? Answers 1. Magnetized needle that aligns itself with the magnetic pull of the Earth (pointing North). 2. You get 2 new (less powerful) magnets. 3. Aurora Borealis (Northern Lights) 4. Electric current 5. Amperes (amps) 6. A magnetic field; the magnetic field reverses as well. 7. A circuit. AM #15 1. Define an electric circuit. 2. What are the 3 components to a circuit? 3. Compare a conductor to an insulator and give an example of each. 4. What happens when you flip a switch? 5. What is resistance? 6. What object is used to help control resistance? 7. Give an example of how resistance is very useful in our lives. 8. Compare a series and a parallel circuit. Use drawings if necessary. Answers 1. The closed path through which charges can flow. 2. Energy source, wires, load. 3. . Conductor moves current easily – the electrons are loosely bound. Copper is an excellent example. Insulator prevents current from moving – the electrons are tightly bound. Rubber is an excellent example. 4. The circuit closes and the electrons are free to move. 5. The opposition to the flow of a charge. 6. Resistor 7. Prevents electrical fires. Your toaster would blow up with out resistance! 8. Series connects loads in only one path. Parallel connects to loads on both sides providing multiple paths for current to flow. AM #16 1. What are the characteristics of a superconductor? 2. How does an electric motor function? 3. What is a galvanometer? 4. What is an armature? 5. What is the function of a commutator? 6. How does an electric generator work? Answers 1. No electrical resistance, very efficient, strongly repels magnets, must be kept very cool. 2. Changes electrical energy into mechanical energy. 3. A device, run by an electromagnet that detects current. 4. A coil or loop in a motor that provides movement for a charge. 5. Reverses the direction of a charge. 6. Changes mechanical energy to electrical energy. AM #17 1. What function does a transformer serve? 2. What is ferromagnetic material and how is it used in electromagnets? 3. How does an electromagnet function? 4. What is the coil called that is used in an electromagnet? 5. How can you increase or decrease the power/strength of an electromagnet? 6. Give an example of an electromagnet. Answers 1. Speed up or slows down current as it flows through wires. 2. Material made from iron or nickel that is highly attracted to magnets. It provides the core to an electromagnet. 3. Has 2 poles that act like switches; when attached to an energy source the ferromagnetic material becomes magnetized. 4. solenoid 5. ? Increase or Decrease the number of coils in the solenoid or add a stronger/weaker ferromagnetic material. 6. A crane in a junkyard, but all of your technological devices contain electromagnets. AM #18 1. What does the law of electric charges state? 2. How are an electric force and an electric field related? 3. Describe 3 ways to charge an object. Give examples. 4. What kind of device can detect a charge? 5. Explain static electricity and electric discharge. 6. In relation to electricity, what does it mean to be grounded? 7. Compare AC to DC. Answers 1. Like charges repel, opposites attract. 2. An electric force creates an electric field. 3. Friction – rubbing balloon on your head and sticking it to the wall (wiping electrons); Conduction – building up electrons on your feet and then touching a metal doorknob (charge transfers by direct contact); Induction – charge happens when an object is exposed to another charge (Van Degraff Generator) 4. Electroscope 5. Charge at rest on an object; touching a conducting object (doorknob) transfers the charge (discharge). 6. Electric current to transferred to the ground via wires. 7. AC – Alternating Current – moves in 2 directions; DC - Direct Current – moves in 1 direction. AM #19 1. 2. 3. 4. What is voltage and how it related to energy? What unit is used to express voltage? Why do batteries vary in voltage? How does resistance factor in with insulators and conductors? 5. If you wanted maximum voltage what kind of wire would you want? Does temperature play a part? 6. What does Ohm’s Law state? 7. What unit to we use to measure resistance? Answers 1. Voltage is the amount of energy needed to push a charge through a wire 2. volts 3. The vary in need and size. 4. Conductors have low resistance; Insulators have high resistance. 5. Thick, short wires in a cool setting is ideal! 6. The ratio of voltage to current is constant and referred to as Resistance. 7. An Ohm - Ω AM #20 1. Define electric power. What unit is used to express electric power? 2. One kilowatt (kW) equals how many watts? 3. Give examples of series and parallel circuits. 4. What is a fuse? 5. How are circuit breakers used in our homes? Answers 1. The rate at which electrical energy is changed into other forms of energy. (Plug in a lamp and it changes into light and thermal energy). Unit is the watt (W) or kilowatt (kW). 2. 1000 3. Series – old Christmas tree lights and burglar alarms; Parallel – circuitry in a home or building 4. Small, thin piece of metal that expands and opens a circuit to prevent the flow of charge. 5. To prevent electrical fires; a safety net.