4. Electrostatics & Electrodynamics Flashcards
Any material that completely blocks current flow is considered a(n):
Isotope
Metal
Conductor
Insulator
Insulator
Current that changes direction several times per second best describes:
Alternating current (AC)
Motion current (MC)
Direct current (DC)
Alternating current (AC)
Current that flows in only one direction along a conductor is called:
Alternating current (AC)
Direct current (DC)
Motion current (MC)
Direct current (DC)
All discussions of electricity are associated with:
Negative charges
Positive charges
Neutral charges
Negative charges
A material that under some conditions will allow current flow and under others will stop current flow is called a:
Semiconductor
Conductor
Insulator
Semiconductor
A metallic conductor, such as copper wire or aluminum, is the most common pathway provided for the movement of electrical current flow. The atoms of metallic conductors allow the valence electrons to:
drift and move easily
stay frozen so they are unable to move
convert into protons
create a vacuum
drift and move easily
The unit of current is:
Electromotive force (emf)
Volt (V)
Ohm (Ω)
Ampere (A)
Ampere (A)
An atom that has the ability to transmit electric current is called a(n):
Conductor
Volt
Insulator
Amp
Conductor
Electrification by induction is best described as:
Electrical fields acting upon each other without contact.
The transfer of electrons when one object rubs against another.
The time required for a quantity of radioactivity to be reduced to 1/2 its original value.
The transfer of electrons when two objects touch.
Electrical fields acting upon each other without contact.
As a charged object gets further away from an uncharged object, the influencing charge decreases as the distance between the two:
Decreases
Increases
Stays the same
Increases
When a circuit allows each individual component (resistor) its own individual branch, it is called a:
series circuit
compound circuit
tandem circuit
parallel circuit
parallel circuit
Using Ohm’s law, calculate the current of a circuit when the voltage is 100 Volts and the resistance is 5 Ω.
500 amps
20 amps
.5 amps
50 amps
20 amps
The ability of an atom or material to conduct electrons (allow current flow) include:
- quantity of electrons in the valence shell (an atom with a +1 valence is a good conductor)
- distance the valence electrons are from the nucleus (the farther the valence electrons are from the nucleus, the better the conductor)
- temperature (as the temperature of the conductor increases, the better the conductor)
1 only
1 and 2
2 and 3
1, 2, and 3
1 and 2
Electrical charges in motion are best described as:
Electrodynamics
Potential energy
Electrostatics
Resistance
Electrodynamics
The process of electron charges being added to or subtracted from an object is called:
Electrostatics
Resistance
Electrification
Electrodynamics
Electrification
The number of electrons that pass a given point per second is represented by the symbol:
A
V
Ω
P
A
As the cross-sectional diameter of a conductor increases, resistance will:
Increase
Conductor length has no effect on resistance
Stay the same
Decrease
Decrease
As the length of a conductor increases, resistance will:
Stay the same
Decrease
Conductor length has no effect on resistance
Increase
Increase
Using Ohm’s law, calculate the voltage of a circuit when the current is 5 Amps and the resistance is 20 Ohms:
4 Volts
100 Volts
10 Volts
.25 Volts
100 Volts
Electricity is best described as the movement and distribution of:
Nucleons
Electrons
Protons
Neutrons
Electrons
When referring to electricity, electrons generally move from an atom’s:
Outermost shell
Nucleus
Innermost shell
Outermost shell
According to the laws of electrostatics, the greatest concentration of charges will reside on the surface of a conductor where the curvature is:
Longest
Straightest
Flattest
Sharpest
Sharpest
What is the power rating expressed in watts (W) with a circuit that operates using 10 amperes and 220 volts?
2,200 W
22 W
.045 W
4,400 W
2,200 W
The amount of opposition to the current in a circuit is called the:
Voltage (V)
Electromotive force (emf)
Resistance (Ω)
Power (W)
Resistance (Ω)
Using Ohm’s law, calculate the resistance of a circuit when the current is 50 amps and the voltage 240 volts:
2.4 Ω
12,000 Ω
4.8 Ω
.20 Ω
4.8 Ω
