Ch. 3 Electricity Flashcards
The resistance in a wire decreases as its:
Diameter increases
If the total resistance in a circuit is 9 ohms and the total voltage is 3 volts, the current it:
1/3 amperes.
V=IR
If a DC circuit is:
a. In series, the currents are different for each component
b. In series, the voltages are the same for each compartment
c. In parallel, the currents are equal for all paths of the circuit
d. In parallel, the voltages are equal for all paths of the circuit
d. In parallel, the voltages are equal for all paths of the circuit
Electric current is defined as:
Charge/time
Coulomb’s law of electrical forces is mathematically described as:
F=q1q2/r^2
A current of 2 amperes and a resistance of 8 ohms require what voltage in a series circuit?
16 volts
V=IR
When an electric current flows through a wire with resistance, energy is:
liberated as heat
Ohm’s law is mathematically described as:
R=V/I
or V=IR
Electric potential is measured in:
Volts
Electric insulators:
Inhibit movement of electrical charge
If 20 volts of potential difference causes a current of 5 amperes to flow in a parallel circuit, the resistance produced is:
4 ohms
V=IR
When the atomic valence and conductance bands overlap,
Electrical flow easily occurs
A charge would lost most of its energy when it passes through a:
Resistor
If the distance between two electrical charges is doubled, the force between them is:
Decreased by 1/4
A 100 W light bulb with an amperage of 0.91 A is operating at a potential difference of:
110 volts
An ampere is:
Coulomb/sec
Resistance is:
The opposition to the flow of electrons
The charge on each of two objects is doubled, and they are moved twice as far apart. The force between them is:
Unchanged
A circuit has a current of 2 amperes and a resistance of 4 ohms. The maximum power that can be delivered is:
16 Watts
V=IR
P=IV
or P=I^2(R)
The unit of electrical power is:
Watt
If 10 coulombs pass a point in 2 seconds, the current is:
5 amps (Couloumb/second)
In a parallel circuit,
The voltage is equal across all branches of the circuit.
In a battery circuit with several resistors of different values connected in series,
a. The voltage drop is the same across all the resistors
b. The current through each resistor is different
c. The power dissipated through each resistor is the same
d. None of the above
d. None of the above
If a conductor is positively charged, it:
Is deficient in electrons
The milliampere (mA) is a unit of:
Current
Neon lights illustrate the fact that electrons will flow:
In a gaseous environment
All of the following choices are considered good metallic electrical conductors EXCEPT:
a. Gold
b. Silver
c. Carbon
d. Copper
c. Carbon
The current flow from a dry cell battery source would be:
Direct current
Electrical components possess a negative and a positive side. This polarity permits the application of:
An electromotive force (emf) to enable current flow
When 6.24 x 10^18 electrons travel in one second producing a joule (j) of work,
One volt has been created
