The resistivity of potentiometer wire is 40 × 10 - 8 Ω m and its area of cross-section is 8 × 10 - 6 m 2 . If 0 . 2 A current is flowing through the wire, the potential gradient of the wire is

R = ρ l A ∴ R l = ρ A = 40 × 10 - 8 8 × 10 - 6 = 5 × 10 - 2 V l = I R l = 0.2 × 5 × 10 - 2 = 10 - 2 V m - 1

Physics - Current Electricity Question with Solution | TestHub

PhysicsCurrent ElectricityElectrical instrumentEasy2 minPYQ_2020

PhysicsEasysingle choice

The resistivity of potentiometer wire is $40 \times 10^{- 8} Ω m$ and its area of cross-section is $8 \times 10^{- 6} m^{2}$ . If $0.2 A$ current is flowing through the wire, the potential gradient of the wire is

Options:

Answer:

Solution:

$R = \frac{ρ l}{A}$

$∴ \frac{R}{l} = \frac{ρ}{A} = \frac{40 \times 10^{- 8}}{8 \times 10^{- 6}} = 5 \times 10^{- 2}$

$\frac{V}{l} = \frac{I R}{l} = 0.2 \times 5 \times 10^{- 2} = 10^{- 2} V m^{- 1}$

Stream:NTA_ABHYAS_NEETSubject:PhysicsTopic:Current ElectricitySubtopic:Electrical instrument

⏱ 2mℹ️ Source: PYQ_2020

Doubts & Discussion

Loading discussions...