Chapt 7_8 8th Sci Word Scramble
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Question | Answer |
The building block of matter | Atom |
All things are made of these | Atoms |
Particle in an atom with a NEGATIVE charge | electron |
Movement of these causes electricity | electrons |
Particle in atom with a POSITIVE charge | proton |
Protons are located in the | nucleus |
A proton (does, does not) move | does NOT move |
Particle in the nucleus of an atom with NO charge | neutron |
The center of the atom which contains protons and neutrons | nucleus |
Objects with opposite charges (- +) | attract |
Objects with like charges (- -) (+ +) | repel |
Build up of electrons in one area due to the gain or loss of electrons when objects rub together | Static electricity |
The rate of the flow of electrons through a conductor | current |
Material that allows electrons to flow easily | Conductor |
Water or copper metal are examples of this | Conductor |
Materials that resist the flow of electrons | Insulator |
What happens when you get a shock from a door knob after walking across a carpet? | Electrons move from the carpet to your body. Because your body has a negative charge, when you touch the door knob (conductor), the electrons jump to it. |
Why does your hair stand up when you pull a wool sweater over your head? | Electrons from the sweater move onto the hair strands. The like charges on the strands repel each other, making them spread apart. |
The flow of electrons | electric current |
Why should you avoid trees in an electrical storm? | They are high objects, and attract electrical strikes |
Why should you avoid holding a golf club in an electrical storm? | Metal objects are good conductors of electricity, and attract electrical strikes |
Why is it safe to be in a car in an electrical storm? | The car is connected to the ground, and will “ground” an electrical strike. The electrons will stay on the outside of the car, due to the "shell effect." |
How does a Thundercloud become electrically charged? | Atoms rub against each other as they are caught in up and down drafts, and electrons are knocked off. |
How do the charges align themselves in a Thunderhead? | Positive charges build up at the top of the cloud, negative near the bottom. |
How do the negative charges in a Thunderhead effect the ground? | The ground becomes positively charged as electrons are pushed away. |
The process that causes an object to become positively charged when near something negatively charged | Induction |
What causes lightning? | Electrons accumulated near the bottom of clouds "jump the gap" to the positively charged ground. What we see is the return stroke. |
What causes a Spark? | When electrons "jump the gap" to a positive object. |
What process occurs when a neutral object is given a temporary charge? | Induction |
Negative charges move from the area where there are the ___________ to where there are the ___________. | Greatest/most to Fewest/least |
True or False: Static electricity can build up on a conductor. | False: Static electricity CANNOT build up on a conductor, because a conductor allows the electrons to move (flow) |
What type of material allows negative charges to build up on its surface? | An insulator |
The larger an insulator's resistance, the _________ the current that flows through it | less/smaller |
The measure of how hard it is for current to flow through a material is its ________. | Resistance |
The difference in electric potential between two areas that causes electrons to flow. | voltage |
In a battery, the difference in charge between these two areas creates a current | The positive and negative terminals |
Voltage is measured in | Volts |
Current is measured in | amps |
When electrons move from one object to another, what happens to the objects' charges? | The one the electrons leave becomes positive; the one the electrons enter becomes negative. |
Rubber, glass, and plastic are all what when used in conjunction with electricity. | Insulators |
The charging of an object caused by contact between two objects is called | Conduction |
What causes thunder? | Thunder is caused when air, superheated by lightning, suddenly expands, creating an "explosive" sound wave. |
When electricity is attracted to a conductor which leads to to the earth, we say it has been what? | Grounded |
When conducting materials are arranged in such a way to allow electrons to flow, they form this. | A closed circuit |
What is the difference between a closed circuit and an open circuit? | A closed circuit allows electrons to flow through it. An open circuit, blocked either by an insulator or a gap in the conductors, prevents the flow of electrons. |
What is the scientific term for a "spark"? | Static discharge |
What type of circuit has only one loop for electricity to flow through? | A series circuit |
What is an example of a series circuit? | Older "Christmas tree" lights |
What type of circuit has two or more loops for energy to flow through? | A parallel circuit |
What is an example of a parallel circuit? | Overhead lights at school |
In which type of circuit do all the lights go out if one stops working? | A series circuit |
What are two advantages of parallel circuits? | All the loops get the same voltage and when one circuit breaks, the others continue to work. |
What type of circuits are used in wiring houses? | Parallel circuits |
Why are grounded (three prong) outlets a safety device? | The ground wire prevents shocks/fires by channeling extra voltage to the ground outside the house. |
What is a GFI outlet? | A Ground Fault Interrupter outlet contains a breaker within the outlet that can prevent shocks/overloads. Usually found in areas with water near outlets (kitchens/bathrooms) |
How does a circuit breaker or fuse box work? | When two much amperage begins to flow through a circuit, the breaker trips or the fuse "blows" (burns through its filament), opening the circuit and breaking the flow of electricity. |
What does voltage difference do? | It creates a push that causes charges. Voltage difference is required for current to flow? |
What are the two types of batteries? | Dry cell and Wet cell |
In the lab, we built a battery with a carbon rod and a zinc container. What type of battery was this? | A dry cell battery. |
What two types of current run most electric devices? | AC and DC |
The terms AC and DC stand for what? | Alternating Current and Direct Current |
In what direction do charges flow? | From high voltage to low voltage |
What does resistance change electrical energy to in a light bulb? | Thermal (heat) energy and light |
What is the unit for resistance? | ohms |
How do wall outlets allow electrical current to flow? | There is a voltage difference between the two hole of the outlet, so the current provided by the power plant will flow through wires plugged into the outlet. |
What do we call the interaction between two magnets that increases as the magnets move closer together? | Magnetic force |
The regions of a magnet where forces are strongest are called its _______________ | Magnetic poles |
What do we call the two poles of a magnet? | North and South |
How are the poles of a magnet like the positive and negative poles of a battery? | Just as like charges repel and opposite charges attract, the like poles of a magnet (N-N or S-S) will repel, and opposite poles (N-S) attract. |
The area surrounding a magnet where magnetic forces are exerted is called its ____________ | Magnetic field |
What 3 elements can be magnetic? | Iron (Fe), Cobalt (Co) and Nickel (Ni) |
What do we call the force of attraction or repulsion between certain objects due to motion of electric charges? | Magnetism |
Iron, Cobalt and Nickel all have small areas of like arrangement of electrons. What do we call these areas? | Magnetic domains |
What causes an object to become magnetic? | All the magnetic domains in the object point the same way. |
How can you magnetize an object made of a magnetic material? | Rubbing a magnetic material with another magnet, or passing it through moving electric charges can line up magnetic domains? |
What do moving charges create? | They can create magnetic fields? |
How are magnetic fields related to electricity? | Magnetic fields can make charges move, creating an electric current. |
What do we call a temporary magnet made by placing a piece of iron inside a coil of wire carrying a current? | An electromagnet |
A device made of an electromagnet that spins freely between the poles of a permanent fixed magnet, changing electric energy to mechanical energy, is called what? | An electric motor |
What device produces electric current by rotating a coil of wire within a magnetic field? | A generator |
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