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An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)
(a) No self-heating of RTD is considered
(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.
Correct answer is '454.54, 20'. Can you explain this answer?
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Verified Answer
An RTD has a resistance of 500Ω at 20°C and a temperature co-efficien...
Given α = 0.005 at 0°C
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t = 20°C
Rt20 = 500Ω
Now, Rt = R0 [1 + α (T - T0)]
or 500 = 1.1 R0
or R0 = 500 / 1.1 = 454.54Ω
(a) without heating effect is 454.54Ω
(b) Dissipating constant = 20 m W/°C
Most Upvoted Answer
An RTD has a resistance of 500Ω at 20°C and a temperature co-efficien...
Given data:
- Resistance of RTD at 20°C = 500 Ω
- Temperature coefficient of RTD at 0°C = 0.005/°C
- R1 = R2 = 500 Ω
- Bridge supply = 10 V
(a) No self-heating of RTD is considered:
At 0°C, the resistance of RTD can be calculated using the temperature coefficient as follows:
R0 = R + αRΔT
where R0 = resistance of RTD at 0°C, R = resistance of RTD at 20°C, αR = temperature coefficient of RTD, and ΔT = change in temperature from 20°C to 0°C
R0 = 500 + (0.005)(500)(-20) = 400 Ω
To null the bridge, the resistance of R3 can be calculated as follows:
R3 = R1R0/R2 = (500)(400)/500 = 400 Ω
To null the bridge, the value of R3 is 400 Ω.
(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C:
The power dissipated by the RTD can be calculated using the following formula:
P = (ΔT)/K
where P = power dissipated by the RTD, ΔT = change in temperature from ambient temperature, and K = dissipation constant of the RTD
Let ΔT be the change in temperature due to self-heating, then
P = ΔT/K = 20 mW/°C
ΔT = (20)(10^-3)(1/R0) = (20)(10^-3)(1/400) = 0.05°C
The resistance of the RTD at the new temperature can be calculated as follows:
R1 = R0 + αRΔT = 400 + (0.005)(400)(0.05) = 402 Ω
To null the bridge, the resistance of R3 can be calculated as follows:
R3 = R1R0/R2 = (402)(400)/500 = 321.6 Ω
To null the bridge, the value of R3 is 321.6 Ω.
Therefore, the values of R3 to null the bridge when no self-heating is considered and when self-heating is considered with a dissipation constant of 20 mW/°C are 400 Ω and 321.6 Ω respectively.
- Resistance of RTD at 20°C = 500 Ω
- Temperature coefficient of RTD at 0°C = 0.005/°C
- R1 = R2 = 500 Ω
- Bridge supply = 10 V
(a) No self-heating of RTD is considered:
At 0°C, the resistance of RTD can be calculated using the temperature coefficient as follows:
R0 = R + αRΔT
where R0 = resistance of RTD at 0°C, R = resistance of RTD at 20°C, αR = temperature coefficient of RTD, and ΔT = change in temperature from 20°C to 0°C
R0 = 500 + (0.005)(500)(-20) = 400 Ω
To null the bridge, the resistance of R3 can be calculated as follows:
R3 = R1R0/R2 = (500)(400)/500 = 400 Ω
To null the bridge, the value of R3 is 400 Ω.
(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C:
The power dissipated by the RTD can be calculated using the following formula:
P = (ΔT)/K
where P = power dissipated by the RTD, ΔT = change in temperature from ambient temperature, and K = dissipation constant of the RTD
Let ΔT be the change in temperature due to self-heating, then
P = ΔT/K = 20 mW/°C
ΔT = (20)(10^-3)(1/R0) = (20)(10^-3)(1/400) = 0.05°C
The resistance of the RTD at the new temperature can be calculated as follows:
R1 = R0 + αRΔT = 400 + (0.005)(400)(0.05) = 402 Ω
To null the bridge, the resistance of R3 can be calculated as follows:
R3 = R1R0/R2 = (402)(400)/500 = 321.6 Ω
To null the bridge, the value of R3 is 321.6 Ω.
Therefore, the values of R3 to null the bridge when no self-heating is considered and when self-heating is considered with a dissipation constant of 20 mW/°C are 400 Ω and 321.6 Ω respectively.
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An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer?
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An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer?.
An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer?.
Solutions for An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? in English & in Hindi are available as part of our courses for GATE.
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An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer?, a detailed solution for An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? has been provided alongside types of An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice An RTD has a resistance of 500Ω at 20°C and a temperature co-efficient of 0.005/°C at 0°C. The RTD is used in a Wheatstone bridge circuit with R1 = R2 = 500Ω. The variable resistor R3 nulls the bridge. If the bridge supply is 10 V and the RTD is in a both of 0°C, find the values of R3 to null the bridge when (2000)(a) No self-heating of RTD is considered(b) Self-heating of RTD is considered and the dissipation constant of the RTD is 20 mW/°C.Correct answer is '454.54, 20'. Can you explain this answer? tests, examples and also practice GATE tests.
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