Question

Find the percentage error in kinetic energy of a body of mass $m=60.0\pm 0.3g$ and moving with a velocity of $v=25.0\pm 0.1cm/s$

Answer 1

The % uncertainty in mass = $0.3/60\times 100=0.5$%

and % uncertainty in mass = $0.1/25\times 100=0.4$%

KE = $\frac{1}{2}$ mv${}^2$

KE = m + $2$v

KE = $0.5$ + $2\times 0.4$

KE = $1.3$% uncertainty.