Elec 02-01 to Elec 02-03 Electrical Elements

State which of the following is false. The capacitance of a capacitor

• is proportional to the crosssectional area of the plates
• is proportional to the distance between the plates
• depends on the number of plates
• is proportional to the relative permittivity of the dielectric

A resistor with a power rating of 25W is most likely a

• carbon-composition resistor
• metal-film resistor
• surface-mount resistor
• wire-wound resistor

A significant advantage, in some situations, of a toroidal coil over a solenoid is

• The toroid is easier to wind
• The solenoid cannot carry as much current
• The toroid is easier to tune
• The magnetic flux in a toroid is practically all within the core

What formula would calculate the total inductance of inductors in series?

• LT = L1 / L2
• LT = L1 + L2
• LT = 1 / L1 + L2
• LT = 1 / L1 x L2

What is the ability to store energy in a magnetic field called?

• Admittance
• Capacitance
• Resistance
• Inductance

How would you calculate the total capacitance of three capacitors in parallel?

• CT = C1 + C2 / C1 - C2 + C3
• CT = C1 + C2 + C3
• CT = C1 + C2 / C1 x C2 + C3
• CT = 1 / C1+1 / C2 + 1 / C3

What is the ability to store energy in an electric field called?

• Inductance
• Resistance
• Tolerance
• Capacitance

With permeability tuning, moving the core further into a solenoidal coil:

• Increases the inductance
• Reduces the inductance
• has no effect on the inductance, but increases the current- carrying capacity of the coil
• Raises the frequency

Which of the following statement is false?

• An air capacitor is normally a variable type
• A paper capacitor generally has a shorter service life than most other types of capacitor
• An electrolytic capacitor must be used only on a.c. supplies
• Plastic capacitors generally operate satisfactorily under conditions of high temperature

What electrical parameter is controlled by a potentiometer?

• Inductance
• Resistance
• Capacitance
• Field strength