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# Physics 4-26

Question | Answer |
---|---|

The charge of an electron is | Negative |

Atomic Nuclei of almost all elements consist of | Protons and neutrons |

Two like charges | repel each other |

Protons and electrons | attract each other |

The fundamental force underlying all chemical reactions is | Electrical |

Electrical forces between charges are strongest when the charges are | close together |

Coulombs law says that the force between any two charges depends | Both A and B |

Two charges are separated by a certain distance. If the magnitude of each charge is doubled, the force on each charge is | Quadrupled |

When the distance between two charges is halved, the electrical force between the charges | Quadruples |

The net charge of a non ionized atom | is zero |

A positive ion has | more protons than electrons |

If you comb our hair and the comb becomes positively charged, your hair becomes | Negatively charged |

In a good insulator, the electrons are usually | Semi-free to move around |

Objects can be charged by | All of the above |

Charge carriers in metal are electrons rather the protons, because electrons are | all of the above |

To be safe in the unlikely case of a lighting strike, it is best to be inside a building framed with | steel |

A negatively charged rod is brought near a metal can the rests on a wood table. You touch the opposite side of the can momentarily with your finger. The can is then | positively charged |

An electroscope is charged positively, as shown by foil leaves that stand apart. As a negatively charged rod is brought close to the electroscope, the leaves | move closer together |

Lighting bolts occur between | Both A and B |

When a charged cloud passes overhead, the ground below is charged by | Induction |

Bring a charged object near a conductor and then momentarily touch the conductor. This demonstrates charge by | induction |

The reason a charged balloon will stick to a wall is that | induced opposite charged in the wall are closer than the other wall charges |

Two charged particles held close to each other are released, as they move, the force on each particle increases. therefore, the particles have | opposite signs |

Two charged particles held close to each other are released. As the particles move, teh velocity of each increases. Therefore, the particles have | charges that cannot be determined |

A positive charge and a negative charge held near each other are released. As they move, the force on each particle | Increases |

Two charged particles held near each other are released. As they move, the acceleration of each decreases. Therefore,t he particles have | The same signs |

The SI unit of charge is the | Coulomb |

Particle A has twice as much charge as particle B. Compared to the force on particle A, the force on particle B is | the same |

The electrostatic force between two charges located 8 meters apart is 0.10 N. What will the force between these charges when they are located 2 meters apart? | 1.6 N |

A 2-C charge and a 4-C charge attract each other with a 10 N of force. How much will a 2-C charge and a 12-C charge attract each other when placed the same distance apart? | 60 N |

Two charges separated a distance of 1.0 meter exert a 10-N force on each other. If the charges are pushed to a separation of 1/3 meter, the force on each will be | 18.0 N |

two charges separated by a distance of 1 meter exert a 20-N force on each other. If the charges are pulled to a 2 meter separation distance, the force on each charge will be | 5 N |

Two charges separated by a distance of 1 meter exert a 2-N fore on each other. If the magnitude of each charge is doubled, the force on each charge is | 8 N |

In order for there to be a flow of charge from one place to another, there must be a | Both A and B |

In solid conductors, electric current is the flow of | electrons |

Electrons move in an electric circuit... | by interacting with an established electric field |

An ampere is a | Unit of current |

An example of a voltage source is | All of the above |

Electrical resistance in a wire depends on the wires | All of the above |

Electrical resistance in a wire depends on the wire's | All of the above |

COMPARED TO THIN WIRES, ELECTRICAL RESISTANCE IN THICK WIRES IS | less |

For most conductors, as their temperature increases, their resistance | increases |

electrical resistance is measured in | none of the above |

A woman experiences an electrical shock. The electrons making the shock come from | the woman's body |

while you are standing on the ground in your running shoes, the greatest resistance between you and the ground is in | the running shoes |

The primary reason a bird can perch harmlessly on a bare high voltage wires is that | There is no potential difference across the birds feet. |

Alternating current is made by | alternating he direction of voltage of the power source. |

The frequency of AC current in North America is | 60 hertz |

Current from a battery is always | DC |

Where do the electrons come from that produce heat and light in a light bulb? | the bulbs wire filament |

In 2004, the number of electrons to an average American home by an average power utility was | Zero |

When we say an appliance uses up electricity, we really are saying that | electron kinetic energy is changed into heat and other forms of energy |

If you plug an electric toaster rated at 110 V into a 220 V outlet, current in the toaster will be | Twice what it should be |

The resistance of your dry skin is usually around | 100,000 ohms |

Electric power is defined as | current times voltage |

Compared to the filament thickness on a 60 W light bulb, the filament thickness of a 100 W light bulb will be | greater |

Power outlets in our home typically have a potential difference of | 120 V |

When an 8 V battery is connected to a resistor, 2 A of current flows in the resistor. What is the resistors value? | 4 ohms |

The current through a 5 ohm resistor connected to a 150 V power supply is | 30 A |

A 15 ohm resistor has a 5 A current in it. What is the voltage across the resistor? | more than 25 V |

What is the resistance of a toaster that uses 5 A of current when connected to a 120 V power source? | 24 ohms |

When connected to a 110 V power supply, how much current is in a light bulb that has a resistance of 220 ohms? | 0.5 A |

If you accidentally grabbed the prongs of a partially plugged in 120 V electrical plug on a day when your skin resistance was 130,000 ohms, how much current would pass through your body? | .0009 A |

How much power is used by a 12.0V car battery that draws 0.5 A of current? | 6W |

When plugged into a 120 V wall outlet, how much current is used by an electric blanket rated at 140W? | 1.2 A |

A 120 Watt light bulb is connected to a 120 V outlet. how much current is in the light bulb? | 1 A |

A light bulb is plugged into a 120 V outlet and has a 0.7 A current in it. What is the power rating of the light bulb? | 84 W |

A 60 W light bulb and a 100 W light bulb are both rated at 120 V. Which light bulb has the larger resistance? | the 60 W bulb |

A 60 W light bulb and a 100 W light bulb are each connected to a 130 V outlet. Which bulb has more current in it? | the 100 W bulb |

An electric heater is rated at 300 W for use in a 100 V circuit. The circuit breaker in the circuit can handle 12 A of current. How many heater can be safely operated in the circuit? | 4 |

A heater uses 21 A when connected to a 110V line. If the electric power costs 10 cents per kilowatt-hour in the location, the cot of running the heater for 13 hours is ____? | $3.000 |

A power line with a resistance of 9 ohms has a current of 80 A in it. The power dissipated in the line is | 57,600 W |

Suppose energy costs $0.09 per kilowatt-hour. How much would it cost to keep a 40 Watt porch light on all night every night for one month (average month = 30, average night = 10) | $1.08 |

how much voltage is required to make 4 amperes flow through a 12 ohm resistor? | 48 Volts |

A battery does 18J of work on 10 coulombs of charge. What voltage does the battery supply? | 1.8 V |

What is the current in a 60W bulb connected to a 120V source? | 0.5 Amps |

What is the power dissipated by a toaster that has a resistance of 40 ohms and is plugged into a 120 V outlet? | 360 Watts |

A certain bulb with a resistance of 240 ohms is labeled 60 W. For what voltage circuit was this bulb designed? | 120 Volts |

In order to form a electric circuit, you need to have | All of the above |

In order for a current to flow in a circuit, you must have | A complete path for the current |

Electrical resistance is measured in | None of the above |

A closed circuit is a circuit in which charge | can flow |

When two light bulbs are connected in a series, the | same amount of current always flows through each bulb |

The symbol used to represent resistance in a schematic diagram is | a zigzag line |

When resistors are put in a series next to each other, their overall resistance is | Larger than the resistance of any individual resistor |

When resistors are put in a parallel next to each other, their overall resistance is | Smaller then the resistance of any of the resistors. |

As more lamps are put into a series circuit, the overall current in the circuit | decreases |

As more lamps are put into a parallel circuit, the overall current in the circuit | increases |

Compared to the resistance of 2 resistors connected in series, the same two resistors connected in parallel have | less resistance |

When one light bulb in a series circuit containing several light bulbs burns out, the other light bulbs | none of the other bulbs will light up |

When one light bulb in a parallel circuit containing several light bulbs burns out, the other light bulbs | burn the same as before |

In a simple parallel circuit | voltage across each branch is always the same |

In a simple parallel circuit | all of the above |

Electrical devices in our homes are connected in | Parallel |

Fuses and circuit breakers are used to | all of the above |

A short circuit occurs when | the positive wire is connected directly to the negative wire |

Two lamps, one with a thick filament and one with a thin filament, are connected in a parallel to a battery. The voltage is greater across the lamp with the | Both voltages are the same |

Two lamps, one with a thick filament and one with a thin filament, are connected in a parallel to a battery. The current is larger in the lamp with the | Thick filament |

Two lamps, one with a thick filament and one with a thin filament, are connected in a series to a battery. The voltage is greater across the lamp with the | thin filament |

A 60 W light bulb is connected to a 12 V car battery. When another 60 W light bulb is connected in parallel with the first bulb, the battery output energy | doubles |

The total resistance of a 10 ohm resistor and a 7 ohm resistor in series is | 17 ohms |

The total resistance of a 6ohm resistor and a 12 ohm resistor in a parallel is | 4 ohms |

A 60 W light bulb and a 100 W light bulb are both connected in parallel to a 120 V outlet. Which bulb has more current in it? | The 100 W light bulb |

The current through 2 identical light bulbs connected in series is .25 A. The total voltage across both bulbs is 120 V . the resistance of a single light bulb is | 240ohms |

How many 6 ohm resistors must be connected in parallel to create an equivalent resistance of 1 ohm? | 6 |

What is the equivalent resistance of a 30 ohm and a 20 ohm resistor connected in parallel? | 12 |

Two identical resistors in parallel have an equivalent resistance of 7 ohms. If the same resistors were instead connected in series, what would be the equivalent resistance? | 28 |