The power dissipated in a resistor is

PHYSICS · Multi-part · Fermi University Physics · Scientific Practice & Experimental Methods · Uncertainty in measurement · Uncertainty in measurement

Measurement and Method, Ch Propagating uncertainty into the quantity you actually want

Problem

P = I^2R

, with a measured current

I = (0.500 \pm 0.010)\,\mathrm{A}

and resistance

R = (12.0 \pm 0.2)\,\Omega

, each uncertainty a standard deviation and the two quantities measured independently. ((a)) Find the contribution of

I

P

by moving

I

up to

I+u(I)

with

R

fixed, and the contribution of

R

by moving

R

up to

R+u(R)

with

I

fixed. ((b)) Combine these to give

u(P)

and quote

P = \bar P \pm u(P)

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