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erik [133]
3 years ago
12

The filament of a certain lamp has a resistance that increases linearly with temperature. When a constant voltage is switched on

, the initial current decreases until the filament reaches its steady-state temperature. The temperature coefficient of resistivity of the filament is 43 times 10^-3 K^-1. The final current through the filament is one- eighth the initial current. What is the change in temperature of the filament?
a.30100 K
b.378 K
c.1627 K
d.814 K
e.1162 K
Physics
1 answer:
Neporo4naja [7]3 years ago
5 0

Answer:

162.8 K

Explanation:

initial current = io

final current, i = io/8

Let the potential difference is V.

coefficient of resistivity, α = 43 x 10^-3 /K

Let the resistance is R and the final resistance is Ro.

The resistance varies with temperature

R = Ro ( 1 + α ΔT)

V/i = V/io (1 + α ΔT )

8 = 1 + 43 x 10^-3 x ΔT

7 = 43 x 10^-3 x ΔT

ΔT = 162.8 K

Thus, the rise in temperature is 162.8 K.

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Problem:
pav-90 [236]

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Total energy is constant

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Two buses are driving along parallel freeways that are 5mi apart, one heading east and the other heading west. Assuming that eac
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Answer:

101.54m/h

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Feel free to ask for more if needed or if you did not understand something.

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