the resistance of a metalic wire at 0 degree celsius is 5ohm at what temperature its resistance will be 15 ohm
Answers
Answer:
Well, try thinking about it this way: the resistance changed by only
1
Ω
over
50
o
C
, which is a pretty large temperature range. So, I would say it's safe to assume the change in resistance with respect to temperature (
Δ
Ω
Δ
T
) is pretty much linear.
Δ
Ω
Δ
T
≈
1
Ω
50
o
C
Δ
Ω
=
1
Ω
100
o
C
−
50
o
C
⋅
(
0
o
C
−
50
o
C
)
≈
−
1
Ω
Ω
0
o
C
≈
4
Ω
Answer link
Arunraju Naspuri · Stefan V.
Jun 15, 2015
Its resistance at
0
∘
C
is 4 ohm.
Explanation:
R
T
=
(
1
+
α
T
)
R
, where
R
T
=
Resistance at any temperature,
α
=constant of material,
R
=
resistance at Zero degree Celsius.
At 50 degrees Celsius:
R
50
=
(
1
+
50
α
)
R
=
5 ohm
(
1
)
At 100 degrees Celsius:
R
100
=
(
1
+
100
α
)
R
=
6 ohm
(
2
)
At zero degrees Celsius:
R
0
=
(
1
+
0
)
R
R
0
=
R
(
3
)
Determination R from equations
(
1
)
and
(
2
)
** by
(
1
)
(
2
)
⇒
1
+
50
α
1
+
100
α
=
5
6
6
+
300
α
=
5
+
500
α
⇒
α
=
1
200
Use this value in equation
(
1
)
(
1
+
1
200
⋅
50
)
⋅
R
=
5
⇒
5
4
⋅
R
=
5
⇒
R
=
4 ohm
According to equation
(
3
)
, you have
R
0
=
R
=
4 ohm
Therefore, its resistance at
0
∘
C
is
4 ohm
.
Explanation: