What particle has a charge of -1?
an electron
What is the measurement of the pushing power of a current?
volt
This device shows:
A. the large hadron collider (LHC)
B. an atom smasher
C. the most powerful magnet in the world
D. all of these
D. all of these
This changes electricity into mechanical energy. 100
motor
This is a solenoid around an iron core. It is found in nearly all electrical devices.
electromagnet
Which of these devices runs on a Direct Current, charges flow from a battery all the way around.
Which of the following devices contains one or more electromagnets? 98-99
doorbell hairdryer & speakers MRI atom smasher
All of these devices contain electromagnets.
All of these devices contain electromagnets.
Which magnet best shows the magnetic field around the bar magnet. pp. 90-91
B
A magnet that is an iron core wrapped with electrical wire is called a(n): 97
electromagnet
Adding an iron core to a solenoid makes it:
stronger less expensive to operate.
safer less polluting.
stronger
Which atomic model is labeled correctly?
[Double Click]
A
If resistance (ohms) increases and voltage (volts) stays the same, what happens to current (amp)?
[double click]
It decreases.
The greater the distance between two magnets, the ____ the magnetic field.
weaker
This device changes mechanical energy into electricity.
electric generator
___ occurs when a wire moving near a magnet gains an electric current. p.95
circuits induction friction conduction
Induction occurs when a wire moving near a magnet gains an electric current.
Objects with like charges + + OR - -
_____ each other.
repel
Which material has the highest resistance?
rubber nickel iron copper
Rubber has the highest resistance.
What device does this describe?
a steel solenoid inside a glass vacuum that glows white hot when current passes through the solenoid
light bulb
This is a coiled wire with an electric coil that produces a magnetic field. 97
solenoid
To increase the strength of a solenoid, you would:
A. plug up multiple items in the circuit.
B. arrange the resistors of the circuit in a parallel circuit.
C. increase the number of loops or the amount of electric current.
D. arrange the resistors of the circuit in a series circuit.
C. increase the number of loops or the amount of electric current.
A ceiling fan uses .5 Amps and has 220 Ohms. What is the voltage for the fan?
Resistance = Volts / Amps
Amps = Volts / Resistance
Volts = Resistance X Amps
Resistance X Amps = volts
.5 X 220 = 110 V
110 V
A TV set uses 110 V (volts) and 0.9 I (amps). What is the resistance (Ohms) of the TV?
Resistance = Volts / Amps
Amps = Volts / Resistance
Volts = Resistance X Amps
Which picture best shows the domains of a magnet?
D
This device transfers electricity from one circuit to another by changing the voltage level.
transformer
What do we call a device that measures the strength and direction of an electric current in a wire? 98
galvanometer