Electronics - Voltage and Current - Discussion


Which resistive component is designed to be temperature sensitive?

[A]. Thermistor
[B]. Rheostat
[C]. Potentiometer
[D]. Photoconductive cell

Answer: Option A


No answer description available for this question.

Sundar said: (Oct 19, 2010)  
Thermal+Resistor = Thermistor.


So, the resistor value depends on the temperature.

Nidhi Chandra said: (Oct 30, 2010)  
Thermister are used to measure temperature very precisely.

Vrushali Warkhedkar said: (Nov 19, 2010)  
This is type of resistor used to calculate tempreture, this resistor is specialy design for temp measurement.

Uma Maheswararao said: (Dec 31, 2010)  
Here sensitive means temperature effects highly in huge amounts. Thermister can have that property.

Yogeshwari Mahanti said: (Jan 6, 2011)  
Thermister is the positive temperature cofficient so that
thermister is the temperature sensitive.

Vikram Tumkur said: (Jan 25, 2011)  
Thermally sensitive resistor is known as thermistor.

Ravikumar said: (Feb 13, 2011)  
Thermistor is not a positive temperature coefficient. Its an NTC.

"Negative Temperature Coefficient". (ie) If temperature increases the resistor value starts to decrease. Yogeshwari answer is wrong.

Anu said: (Feb 25, 2011)  
Here name it self specifies that thermistor is a temperature varing device.


Swapna said: (Mar 11, 2011)  
Why photoconductive cell, potentiometer, rheostat are not temperature sensitive?

Kawalprit Kaur said: (May 3, 2011)  
Thermal + resistance. Resistance of thermister varies with temperature having -ve temp coefficient.

Sireesha said: (May 8, 2011)  
If temperature increases then resistance value decreases means it is a negative temperature coefficient.

Gayu said: (May 11, 2011)  
Thermistor is a PTC resistor. Its ohmic value directly proportional to the temperature. Yogeshwari is correct only. Ravikumar answer only wrong.

Ajirs said: (May 25, 2011)  
Assuming, as a first-order approximation, that the relationship between resistance and temperature is linear, then:

(Δ R)=k(Δ T),


ΔR = change in resistance
ΔT = change in temperature
k = first-order temperature coefficient of resistance

Thermistors can be classified into two types, depending on the sign of k. If k is positive, the resistance increases with increasing temperature, and the device is called a positive temperature coefficient (PTC) thermistor, or posistor. If k is negative, the resistance decreases with increasing temperature, and the device is called a negative temperature coefficient (NTC) thermistor.

Preeti said: (May 31, 2011)  
A thermistor is a type of resistor whose resistance varies significantly with temperature

Raja said: (Jul 2, 2011)  
Please say correct answer thermistor is PTC or NTC ?

Sundar said: (Jul 2, 2011)  
Thermistors are special solid temperature sensors that behave like temperature-sensitive electrical resistors. No surprise then that their name is a contraction of "thermal" and "resistor". There are basically two broad types, NTC-Negative Temperature Coefficient, used mostly in temperature sensing and PTC-Positive Temperature Coefficient, used mostly in electric current control.

Rohini said: (Jul 2, 2011)  
Thermistors are two types- ptc and ntc. Depending upon their operation they are varied in temperature co-efficient. so no need to confuse frndz :)))))

Raju said: (Jul 9, 2011)  
Thermistors is a type of resister whose resistances varies significantly with temperature. Temperature increasing resistances decreasing.

Amit said: (Jul 16, 2011)  
It is to used measure the internal temperature of electical components.

Keyur said: (Jul 18, 2011)  
What is a need to measure the internal temperature of electical components?

Neelraj said: (Jul 25, 2011)  
To produce the heat that is thermal. The resistor depend on thermal. So its known as thermistor.

Gopiram Verma said: (Jul 28, 2011)  
It is well known that resistance of metallic conductors increases with temperature, while that of semiconductors generally decreases with temperature. Resistance thermometers employing metallic conductors for temperature measurement are called Resistance Temperature Detector (RTD) , and those employing semiconductors are termed as Thermistors.

The NTC thermistors is more common. Essentially, they are made from oxides of iron, manganese, magnesium etc.

The Positive Temperature Coefficient (PTC) thermistor have limited use and they are particularly used for protection of motor and transformer widings.

They have low and relatively constant resistance below a threshold temperature TR, beyond which the resistance increases rapidly. The PTC thermistors are made from compound of barium, lead and strontium titanate.

Keerthi said: (Jul 29, 2011)  
Sundar is correct. There is NTC and PTC types.

Mounika said: (Sep 16, 2011)  
Thermistors can be PTC or NTC according to the temperature.

Aswani said: (Oct 15, 2011)  
Temp=thermal; so it is thermistor.

Bharat said: (Dec 21, 2011)  
Thermistor is a temperature measuring device.

Sreeyush Sudhakaran said: (Feb 18, 2012)  
A thermistor is a type of resistor whose resistance varies significantly with temperature, more so than in standard resistors. The word is a portmanteau of thermal and resistor. Thermistors are widely used as inrush current limiters, temperature sensors, self-resetting overcurrent protectors, and self-regulating heating elements.

Rheostat-Current controling device with resistance coil
Potentiometer-Votage varing and measuring circuit
Photoconductive cell- Produces current when light incident on it

All the above have less temperature coefficents.

Thermistors differ from resistance temperature detectors (RTD) in that the material used in a thermistor is generally a ceramic or polymer, while RTDs use pure metals. The temperature response is also different; RTDs are useful over larger temperature ranges, while thermistors typically achieve a higher precision within a limited temperature range, typically −90 °C to 130 °C.

Chinni said: (Mar 17, 2012)  
Thermister is PTC or not?

S.Lakshmi said: (Mar 22, 2012)  
Thermistor is a resistive component so that is used to temperature.

Niks said: (May 28, 2012)  
Thermistor is available in both the category. It is depending on it application. Whether its NTC PTC.

Jyoti Bharsat said: (Jun 12, 2012)  
Temperature+Resistor = Thermistor.

Swathi said: (Jul 29, 2012)  
Here sensitive means the degree or certainity of o/p for a change in input, temperature change is high so, thermistor is the right answer.

Rajashri B Arsud said: (Jul 30, 2012)  
Thermistor has two types,

1) PTC - Positive temperature co-efficient.

2) NTC - Negative temperature co-efficient.

Kaushal said: (Aug 19, 2012)  
When we are change in temprature and no change in resistor so I call thermister is temp sensitive.

Prafulla said: (Aug 25, 2012)  
Yes, Thermister ans. is correct. It has NTC and PTC depending on the value of 'k'

Tejashree said: (Sep 11, 2012)  
Kaushal's statement is wrong. Temp changes with resistance means thermistor.

K.Dinesh said: (Sep 27, 2012)  
There are two components sensitive to temperature but thermistor is only resistance component between thermistor and photo conductive cell.

Rajthilak said: (Oct 7, 2012)  
Thermistor-thermally sensitive resistor.

Priyahalesh said: (Nov 2, 2012)  
Thermistor has two type.
PTC Thermistor "POSISTOR" (for heaters, motor starters, over current protection, over heat sensing & automotive).
NTC thermistor (for inrush current suppression, temperature sensor / compensation & automotive) are offered.
Thermistor is a temperature measuring device.

Jayalakshmi said: (Dec 28, 2012)  
Thermistor is device designed specially to measure temperature. Hence it is a temperature sensitive component.

Shruthi said: (Feb 19, 2013)  
Thermistor has negative temperature coefficient.

Janu said: (Apr 12, 2013)  
Can anyone please explain what is the use of rheostat, potentiometer, photoconductive cell ?

Thanga Mariappan said: (May 24, 2013)  
Thermistor is a kind of resistor depends upon the coefficient it provides resistance.

1. PTC- if temperature is increased resistance also increases.

2. NTC- if temperature is increased resistance also decreases.

Sravani said: (Jul 17, 2013)  
Note that the question is which one is designed to be sensitive to temperature. And it is thermistor. i.e. , it is designed with the motto to be temperature Sensitive.

However the others may have the sensitivity with temp in practical cases. But they not intendedly designed to be sensitive.

Logeshwaran said: (Aug 3, 2013)  
Thermistor is temperature sensing device.

Naveen Tewari said: (Aug 8, 2013)  
Thermal + resistor = thermistor.

Here thermal indicate that resistor is temperature coefficient.

When temperature increase resistance decrease.

Pradip said: (Oct 6, 2013)  
If temperature increases, resistance value decreases hence it is negative temperature coefficient.

Anjali said: (Nov 2, 2013)  
Rheostat and potentiometer are almost the same. They are variable resistors whose value can be changed by us and does not depend on external parameters.

Photo conductive cells depend light. Similar to LDRs.

Sonukumar said: (Nov 4, 2013)  
Thermistor is a special type of resistor thermal + resistor it is use to measure temperature.

Prerna said: (Dec 10, 2013)  
Thermistors are temperature dependent.

Sushmita Choudhary said: (Jan 27, 2014)  
The resistance of metal conductor increases with increases of temp because it is contain positive temp coefficient. But it we talk about the semiconductor case. Such as carbon decreases as the temp increase.

Sharda Prasad said: (May 28, 2014)  
Thermistor is a kind transducer which converts thermal energy into electrical energy.

Nick said: (Jun 23, 2014)  
Thermistor is special type of resistor.

1. When temperature is increased resistance decrease.
2. When resistance is increase temperature is decrease.

Prathi said: (Sep 13, 2014)  
How to calculate the value of thermistor in airflow detector circuit?

Rakesh Mairembam said: (Feb 6, 2015)  
Thermister can be of two types depending temperature coefficient, k.

If k is negative thermister is then called NTC or negative temp. Coefficient thermistor. And if, k is positive PTC thermistors.

Chhatrapati Raut said: (Feb 13, 2015)  
Thermister are used to measure temperature. And this type of resistor used to calculate temperature.

Manoj said: (Apr 17, 2015)  
Thermistor contain a variable resister. The resister value vary according to the variation on temperature.

Nilesh Pachpor said: (Jun 24, 2016)  
Temperature =1/resistor.

Gopal said: (Jul 8, 2016)  
Because thermister having thermal property and which the component very sensitive due to some radiation which is by using anti static room.

Jagannath said: (Dec 29, 2016)  
Yes, @Manoj is correct.

Rakesh Yadav said: (Jan 25, 2017)  
Thermister is positive temperature coefficient. Its resistance varies with temperature.

Deepak Bammidi said: (Apr 1, 2017)  
Thermistor is a type of resistor whose resistance is dependent on temperature, more so than in standard resistors. The word is a portmanteau of thermal and resistor. Thermistors are widely used as inrush current limiter, temperature sensors. Thermistors are of two opposite fundamental types:.

With NTC, resistance decreases as temperature rises to protect against inrush overvoltage conditions. Commonly installed in parallel as a current sink.

With PTC, resistance increases as temperature rises to protect against overcurrent conditions. Commonly installed in series as a resettable fuse.

Psalmichael said: (Sep 30, 2017)  
Thermal is the measure for Energy (heat or Cool).

Dharmendra said: (Oct 20, 2017)  
NTC thermistors decrease in resistance as the temperature increases. PTC thermistors are Positive Temperature Coefficient resistors generally made of polycrystalline ceramic materials that have a high positive temperature coefficient, which increases in resistance as the temperature increases.

Shreedhar K S said: (Jul 2, 2019)  
ANSWER - Thermistor is right.

Yes, right @Yogesh & Ravikumar.

They asked only which is temperature based resistor, NTC and PTC both are temperature based thermistor resistors it may be an NTC or PTC.

Thermistors are two opposite fundamental types:

1) NTC- Negative Temperature Coefficient. If here temperature increases resistance decreases.

2) PTC- Positive Temperature Coefficient. If here temperature increases resistance also increases.

Ab Ar_4744 said: (Oct 15, 2019)  
@Shreedhar is right,

The kind of thermistor may be what ever, but both NTC and PTC sensitive to temperature.

Post your comments here:

Name *:

Email   : (optional)

» Your comments will be displayed only after manual approval.