Electrical Short Answers to questions

1.       Define the uses of two types of semiconductor materials.

Answer: There are N and P type semiconductors. In N type semiconductor material the majority carriers are electrons and current passes through those electrons. In P type semiconductors holes are majority carriers and current passes through those holes. For forward bias the P type semiconductor is connected to positive voltage and N type semiconductor is connected to negative voltage to ensure current flow.

  2.  Which type of mechanical variable resistance is used on automobiles?

Answer: There are variable resistors used on automobile to translate the mechanical system position in terms of electrical signal or voltage level to system microcomputer. Those are throttle position sensor, accelerator paddle position sensor etc.

3.       Describe what is meaning of open, grounds, short, and high resistance.

Answer: There are three types of faults in electrical circuits which occur normally. These defects are open circuit, short circuit and high resistance fault.

4.       Explain the effect of each type of circuit defect that will have on the operation of the electrical system under defect.

Answer: In open circuit current can’t pass as there is break in the circuit so the circuit wouldn’t operate at all. In grounding a power wire or circuit touches to ground and it creates excessive current flow from power to ground. Short is condition in which electrical circuit or part of circuit makes connection or contact to another circuit or wire. In such a case malfunction of the circuit happens. High resistance is the state of electrical circuit in which un engineered resistance is created or produced naturally in the circuit. Such un engineered resistance is not defined and have no defined value. Due to this un engineered resistance excessive voltage drop produced and it limits the current in the actual circuit due to which the circuit don’t operate properly.

5.       Describe the use of a circuit protection device.

Answer: Circuit protection device like fuse and circuit breaker is used to protect the electrical system from excessive current flow. Also these protective devices are used to isolate the circuit from the remaining system if the circuit undergoes a short circuit.

6.       Define most common types of circuit protection devices.

Answer: There are two very common type of protective devices used in electrical system. Fuse and circuit breaker.

7.       Describe difference between a potentiometer and rheostat.

Answer: Potentiometer is a three terminal device and it is used as voltage divider to translate the mechanical position of a system to the system microcomputer. Rheostat is the type of variable resistance used to limit the system current.

8.       Define the difference between normally open NO and normally closed NC switches.

Answer: Normally open is a type of switch which has open contacts when the switch is at rest or at off position and it has closed contacts when it is activated or at on position. Whereas normally closed or NC is the type of switch which has closed contacts at rest or at off position. It has open contacts when activated or changed to on position.

9.       Describe differences between forward biasing and reverse biasing a semiconductor diode.

Answer: Forward biasing is sate of a diode in which the diode P terminal is connected to positive supply and N is connected to the negative of the supply. In such a circuit configuration the diode conducts and it passed current. The reverse bias is a state of diode circuit in which the diode P is connected to battery negative and N of the diode terminal is connected to the positive of the supply. In such a case the diode doesn’t conduct and wouldn’t pass the current.