A body travels uniformly a distance of `( 13.8 +- 0.2) m` in a time `(4.0 +- 0.3) s`. Find the velocity of the body within error limits and the percentage error.

Explanation

Given distance `s=(13.8 pm 0.2)m`
and time` t=(4.0 pm 0.3) s`
velocity `v=s/t= (13.8)/(4.0)=3.45ms^(-1)=3.5ms^(-1)`
`(Deltav)/(v)= pm "(" (Deltas)/(s)+(Delta t)/(t)")"= pm "("(0.2)/(13.8)+(0.3)/(4.0)")"= pm "("(0.8+4.14)/(13.8xx4.0)")"`
`= pm(4.49)/(13.8xx4.0)= pm 0.0895`
or `Deltav= pm 0.0895xxv= pm0.0895xx3.45= pm 0.3087`
`= pm 0.31`
`:.v=(3.5pm0.31)ms^(-1)`
percentage error in velocity `=(Deltav)/(v)xx100`
`= pm0.0895xx100= pm 8.95% = pm 9%`