Determine the resistance and temperature-coefficient, Electrical Engineering

Assignment Help:

Determine the resistance and temperature-coefficient:

A platinum coil has a resistance of 3.146 Ω at 40oC and 3.767 Ω at 100oC. Determine the resistance at 0oC and the temperature-coefficient of resistance at 40oC.

Solution

Rt  = R0  + α0  R0  (t - t0 )

Take t0 = initial temperature = 0o.

Rt  = R0  + α0  t R0

= R0 (1 + α0 t )

R100 = R0 (1 + 100 α0) at          t = 100 C          ------- (i)

 

And        R40 = R0 (1 + 40 α0 )         at  t = 40oC           ----------  (ii)

From Eqs. (i) and (ii)

3.767 /3.146    = 1 + 100 α0/1 + 40 α0   ⇒ α = 0.00379 pero C

From Eq. (i)

∴ 3.767 = R0  (1 + 100 × 0.00379)

R0 = 2.732,

α40 =   1/( (1/ α0) + (t2  - t1 ) =1/ (1/0.00379) + (40 - 0) = 1/304 per  o C


Related Discussions:- Determine the resistance and temperature-coefficient

Determine frequency of rotor current, A 3 phase, 6 pole induction motor is ...

A 3 phase, 6 pole induction motor is rated at 400hz, 150v, 10h.p., 3% slip at rated power output. The windage and friction loss is 200w at rated speed. With the motor operating at

Find the highest speeds at which linkage would be possible, Q. Two coupled ...

Q. Two coupled synchronous machines are used as a motor-generator set to link a 25-Hz system to a 60-Hz system. Find the three highest speeds at which this linkage would be possibl

Find the force between the wires, Q. A magnetic force exists between two ad...

Q. A magnetic force exists between two adjacent, parallel current-carryingwires. Let I 1 and I 2 be the currents carried by the wires, and r the separation between them. Making u

Bidirectional shift register, Design 2-bit bidirectional shift register? ...

Design 2-bit bidirectional shift register? ## A list of ten 8-bit numbers is located at address $5000. Write a 68000 Assembly program (flowchart and code) to sort those numbe

Describe the processor technology used for embedded system, a. Write the ad...

a. Write the advantages of choosing a single purpose processor over a general purpose processor. b. List out the hardware units that must be there in the embedded systems. c.

Resistance, if the sheet resistance of a tin oxide is 100 ohms, what is the...

if the sheet resistance of a tin oxide is 100 ohms, what is the thickness of the oxide layer?

Explain bimetals, Explain Bimetals. Bimetals : It is made of two metal...

Explain Bimetals. Bimetals : It is made of two metallic strips of not like metal alloys with various coefficients of thermal expansion. At a specific temperature the strip wil

Discuss the properties and uses of alnico, Discuss the properties and uses ...

Discuss the properties and uses of ALNICO. Alnico : It is an alloy of iron, nickel, cobalt and small amount of copper and aluminium. Properties are - 1. Its saturation f

Find the net force experienced by a positive charge q, Q Two charges of equ...

Q Two charges of equalmagnitude 5µC but opposite sign are separated by a distance of 10 m. Find the net force experienced by a positive charge q = 2 µC that is placed midway betwee

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd