Measure of two quantities along with the precision of respective measuring instrument is `A=2.5ms^(-1)+-0.5ms^(-1)`,B=0.10s+-0.01s`. The value of AB will be

Options

A. `(0.25+-0.08)m`
B. `(0.25+-0.5)`m
C. `(0.25+-0.05)`m
D. `(0.25+-0.135)`m

Answer

A

Explanation

`A=2.5ms^-1+-0.5ms^-1`,`B=0.10s+-0.01s`
`x=AB=(2.5)(0.10)=0.25m`
`(trianglex)/(x)=(triangleA)/(A)+(triangleB)/(B)`
`(0.5)/(2.5)+(0.1)/(0.10)=(0.05+0.025)/(0.25)=(0.075)/(0.25)`
`trianglex=0.075=0.08m`
Rounding off to two significant figures.
`AB=(0.25+-0.08)m`