Technical Subject1-25 Flashcards
In resistance color coding, red color is assigned to what value?
2
Which of the following is a unit of electrical pressure?
Volt
What is another name for a secondary cell
Storage cell
How is a voltmeter connected in a circuit ?
Connect in a shunt across the load
In the American wire gauge, as the number of gauge wire increases, the wire diameter_____.
Decreases
A generator May lost residual magnetism because of ______.
Heating
A meter whose needle is initially at the center.
Galvanometer
A universal motor can be operated on which of the following supply currents?
AC or DC currents
A 6-volt lead acid battery has an internal resistance of 0.01 ohm. How much current will flow if the battery has a short circuit ?
600A
Automatic device that operates at preset values is known as _____.
Relay
What is another name for full voltage starting ?
Direct on line
What is the resistance reading of a shorted capacitor ?
Zero resistance
A wire has a diameter of 0.125 inch. What is its cross sectional area in circular mild?
15625
In metric standard, what is the unit of conductor sizes ?
mm sq.
Multimeters consist of a _______.
Voltmeter, current meter and an ohmmeter.
What component of an atom that doesn’t have any electrical charge ?
Neutron
Excitation current is used is used in which of the following motors?
Synchronous motors
A simple ohmmeter consists of a meter movement in series with,
A battery
What is the former name of the American wire gauge ?
Brown and sharpe
What resistance must be connected across a 4 - ohm resistance in order to give an equivalent resistance of 3 ohms?
12 ohms
When using ohms law E divided by I would solve for _______.
Resistance
Modern contact surfaces are made from what alloys?
Silver
On a simple ohmmeter, the zero ohm mark is _____ of the scale.
Far right
Two resistances of 8 and 10 ohms respectively are connected in parallel and take a total current of 9 A. What is the current flowing in the 8-ohm resistance ?
5A
How do you call a diagram showing the physical location of the components such as coils, contacts, motors and the like in their actual positions?
Wiring diagram
An electric iron takes 3.5 A. If the heating element has a resistance of 40 ohms, what is its power consumption?
0.49 kW
What is the purpose of constructing a lead acid cell into a multiple plate cell ?
To increase the capacity of the cell.
The continuity of a winding coil may be determined by measuring the resistance of the coil. If the winding is_____.
Open
An instrument used to measure the state of electrical charge in a storage battery
Hydrometer
Determine the reactance of a 50 micro farad capacitor. At 60 Hz.
53.06
In a large alternator, which of the following is normally negligible?
Resistance of the winding
